After looking over Monsters of the Multiverse it looks like they got rid of the recovery condition for short rest abilities on all the playable races and replaced them with being able to use them a number of times equal to your proficiency bonus per long rest. It looks like they are trying to get rid of short rests in preparation to 5.5e. I wonder if they are trying to get rid of it and how it would affect & rebalance warlocks.

Changes to playable races doesn’t mean changes to classes and subclasses. I would doubt it due to backwards compatibility for the classes. But who knows 

Most of the recent subclasses have also generally been avoiding short rest refresh of powers.  I think they will move abilities out of the short rest refresh but change the mechanics of what you can do with your hit die on a short rest besides HP recovery.

I have no idea how they will rebuild the Warlock without a short rest mechanic.

The more I look at it the more I think you might be correct, at least in part. I don’t know if they will revamp all of the classes in the 2024 PHB to get rid of short rests completely. Or remove short rests from the game. But I can see them steering away from relying so much on SR abilities since the number of SR groups use can vary so much.

In theory they assumed a certain number of short rests a day for balancing abilities. But I think the reality is, from player feedback, that SR are not used nearly as much as they had anticipated. LR use is probably fairly standard across most groups so balancing for those is easier. 

The problem is that SRs are spammed, not that they're not used enough.  WOTC gave PCs a reason not to spam long rests but just didn't with short rests, which is fundamentally why a sorlock with access to greater restoration (which is trivial - 2 sorcerer subclasses, a race, and a background all grant that) is so powerful a DM is usually forced to violate the RAW to deal with it.  The ideal solution is capping SRs per LR.

Quote from quindraco >>

 sorlock with access to greater restoration (which is trivial - 2 sorcerer subclasses, a race, and a background all grant that) is so powerful a DM is usually forced to violate the RAW to deal with it.  

You don't need to violate RAW, you just need to steal his diamond powder.  

Simple slight of hand should do the trick.

That said RAW includes gritty rest optional rules which makes long rests function like short rests and you can disrupt the parties rest with monsters, so I don't see it as an unsolvable problem.

It is very difficult to interrupt a long rest with combat:
"If the rest is interrupted by a period of strenuous activity — at least 1 hour of walking, fighting, casting spells, or similar adventuring activity — the characters must begin the rest again to gain any benefit from it."

You need to get to an hour of interruption for the rest to be null and void.

While the game is designed for short rests to be interrupted, long rests were not designed that way.

I, for one, welcome our 12 5th level spells slots per day. /s

They're doing something with short rests. I don't think that having classes recover on different rest types is doing anything helpful for the game.
The archetypical adenturing day has ~2 short rests. That's far from a guarantee. Usually when you can short rest, you can also long rest. In my experience players tend to skip short rests very often in favour of long rests.
That's just ending up making short rest players feel bad, always walking around with 1/3 the resources of the long rest classes.
A shared rest type for recovery  makes the most sense for group play.

What they're going to do with Warlock?
My bet is on either inflating spell slots by 200% to replace short rests from the get go, or giving them an ability like the Capstone that lets them refresh their powers x times a day.

The stat blocks for NPC Warlocks in the new Mordenkainen's book look very different from the old Warlock stat blocks. IMHO they have a lot of very interesting changes, and seeing them makes me wonder if these are an indication of what's in store for the Warlock in 5.5E. I rather hope they are.

It seems to me that they could go with keeping the current number of pact slots and give warlocks the ability to recover a slot by using an action proficiency bonus times per long rest. Having to waste an entire action to do this in combat would usually mean that it would only be used between encounters and in general they would land up with roughly the same number of spells per day as if they took one or two short rests.

I hope they will rework the short rest mechanic. Its silly to have half group refill ressources every long rest and other half with short rests. You always have to wait for the one warlock to recover his spells.

Warlock could get spell slots equal to "spell slots equal to proficiency bonus, per combat".

Really, the underlying problem here is that short rests were meant to help convert 4e AEDU to 5e's "3.5e lite" paradigm; At-will is cantrips & normal attacks, Encounter recharges on short rest, Daily recharges on long rest, and Utility is ritual casting.  Half the classes were designed with this in mind, and intended to need to use their "encounter powers" in every encounter, so that parties would want to take a breather after every 1-2 fights... but they underestimated how easily casters could end encounters if they went all out, and gameplay kinda warped around that for a lot of groups.  Most casters typically don't have short rest recharge features, so groups that move at the casters' pace don't bother with short rests, which in turn hurts martials, Warlocks, and other SRR classes.

One solution would be to just follow along with casters unbalancing the game, and rebalance it around their playstyle, and it does seem that it's the solution they're going with.  Personally, I'd rather they give LRR casters something that recharges on short rests (maybe they can convert a hit die or two into low-level slots during a short rest?), give everyone access to at least one or two martial maneuvers that recharge on short rest (maybe accessible by background, and doesn't need to be offensive; I could see, e.g., Entertainer getting an evasive AC-increasing maneuver or an Acrobatics- or Performance-based skill maneuver), or similar things that would encourage people to take more short rests.

It is very difficult to interrupt a long rest with combat:
"If the rest is interrupted by a period of strenuous activity — at least 1 hour of walking, fighting, casting spells, or similar adventuring activity — the characters must begin the rest again to gain any benefit from it.

if only they had thought this thru in terms of the order things are listed in - strenuous activity - fighting, casting spells, at least one hour of walking or similar adventuring activity Which is what I think they meant (RAI) though it’s clearly not RAW.

I hope they will change the rules to Long Rests so that, instead of regaining all your HP and half your Hit Dice every Long Rest, that they invert it so you regain half your HP and all of your Hit Dice every LR. That right there would go a long, long way towards incentivizing all PCs to want to take the recommended 1-2 Short Rests per adventuring day, and justify shifting more of these other things to Long Rest refreshes for balance purposes.

Quote from Wi1dBi11 >>

It is very difficult to interrupt a long rest with combat:
"If the rest is interrupted by a period of strenuous activity — at least 1 hour of walking, fighting, casting spells, or similar adventuring activity — the characters must begin the rest again to gain any benefit from it.

if only they had thought this thru in terms of the order things are listed in - strenuous activity - fighting, casting spells, at least one hour of walking or similar adventuring activity Which is what I think they meant (RAI) though it’s clearly not RAW.

 
I believe that RAW does technically reflect that RAI interpretation because of the punctuation. If it read as follows it would indicate an hour of any of the listed activities:

”If the rest is interrupted by a period of strenuous activity — at least 1 hour of: walking, fighting, casting spells, or similar adventuring activity — the characters must begin the rest again to gain any benefit from it.”

But it doesn’t, and that missing colon means the “1 hour of” only applies to anything before the first comma.

I do agree with you however that things would have been much clearer if they had written them in the order in which you suggest.

Quote from IamSposta >>

I hope they will change the rules to Long Rests so that, instead of regaining all your HP and half your Hit Dice every Long Rest, that they invert it so you regain half your HP and all of your Hit Dice every LR. That right there would go a long, long way towards incentivizing all PCs to want to take the recommended 1-2 Short Rests per adventuring day, and justify shifting more of these other things to Long Rest refreshes for balance purposes.

 I agree. That would also encourage more downtime activities, so they wouldn’t immediately jump back into combat the next day. (How do hit dice really work, anyway?)

Not to be too off-topic, but I wonder how much of the issue with short rests is that the idea of long rest is almost into sacred cow territory. I notice that in the past even with groups not really familiar with D&D they gravitated towards a long rest even if the one caster were only missing a single spell slot and the others were missing a small amount of health.

Quote from VoidFlam3 >>

Quote from IamSposta >>

I hope they will change the rules to Long Rests so that, instead of regaining all your HP and half your Hit Dice every Long Rest, that they invert it so you regain half your HP and all of your Hit Dice every LR. That right there would go a long, long way towards incentivizing all PCs to want to take the recommended 1-2 Short Rests per adventuring day, and justify shifting more of these other things to Long Rest refreshes for balance purposes.

 I agree. That would also encourage more downtime activities, so they wouldn’t immediately jump back into combat the next day. (How do hit dice really work, anyway?)

 
The way they work is, on a Short Rest you can choose to spend Hit Dice one at a time to regain health. You do it one at a time to prevent underspending and/or overspending them. Whenever you spend a Hit Die you roll it and add your Con modifier to the result, and that sum gets added to your current HP. When you have 0 Hit Dice remaining you can spend no more until you regain Hit Dice.

For example, most characters have d8s for their Hit Dice. So most characters would spend a Hit Die, roll 1d8 and add their Con mod to the result and regain that many HP. (Sorcerers and Wizards would instead roll 1d6; Fighters, Paladins and Rangers would roll 1d10; and Barbarians would instead roll 1d12.) After that the player would decide if they want to spend another Hit Die and repeat the process until either they are satisfied with their current HP, or out of Hit Dice.

Whenever you take a long rest you regain half your Hit Dice up to your maximum. That’s not half your spent Hit Dice, but half of your total Hit Dice.

So, for example, a 6th level character regains 3 Hit Dice every long rest, an 8th level character regains 4 Hit Dice every long rest, etc.

The issue with that system is that people tend to hoard their Hit Dice and spend them very miserly to keep themselves topped off after every Long Rest, which only serves to make people skip short rests and only take them sparingly and instead take long rests whenever possible. That is what leads to that “sacred cow” mentality that Bran mentioned above.

My proposed change would have the opposite effect of encouraging people to take short rests more often in between long rests. That’s because the perception of Hit Dice would change from something precious to be hoarded to being a “free” resource, and the impression of HP would shift from being the free resource they currently are to being something to top-off as often as possible. So people would want to take short rests to spend their “free” resource of Hit Dice for healing because they wouldn’t get the automatic top-off on their HP every long rest anymore.

Make sense? 

Thank you, Spotsa! I do like the idea of only half hp at every long rest, I’m definitely home-brewing that into my campaign.