OK - Looking for anything that clarifies the following;

Aspect of the Moon says you can spend all 8 hours of a long rest doing LIGHT ACTIVITY

Light Activity: reading, talking, eating, or standing watch for no more than 2 hours.

So - from what I understand from this, While you can be awake and alert, you can not actually keep watch for more than two hours of your long rest. Does this sound right to everyone else?

I'd read it as an exception to the rule as it is specifying you can do those light activity actions but for 8 hours instead of 2.

Does concentrating on a spell (not casting it) qualify as "light activity"? Since you dont fall unconscious during your rest, you should be able to maintain concentration on a spell you cast before hand during your rest, but would the act of doing so be so strenuous that it prevents you from gaining the rest's benefits? I heard recently that there was a Crawford tweet giving the opinion that Elves could maintain concentration on a spell during their Trance variant of a rest, but I cannot find the source on that right now. 

PHB text for a Long Rest: "A long rest is a period of extended downtime, at least 8 hours long, during which a character sleeps for at least 6 hours and performs no more than 2 hours of light activity, such as reading, talking, eating, or standing watch. 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."

Text for Aspect Of The Moon: "To gain the benefits of a long rest, you can spend all 8 hours doing light activity, such as reading your Book of Shadows and keeping watch."

Seems pretty clear. With Aspect Of The Moon, you can keep watch all night as long as you aren't interrupted by an hour of strenuous activity. Thankfully, most battles are measured in minutes as most, so a midnight ambush isn't likely to reset your Long Rest. Of course, if you end up having to flee, that could change. Casting spells would also mean ritual casting, so if you're going to spend some time at night Identifying a bunch of stuff, make sure it takes less than an hour. :)

Quote from Kaboom979 >>

Does concentrating on a spell (not casting it) qualify as "light activity"? Since you dont fall unconscious during your rest, you should be able to maintain concentration on a spell you cast before hand during your rest, but would the act of doing so be so strenuous that it prevents you from gaining the rest's benefits? I heard recently that there was a Crawford tweet giving the opinion that Elves could maintain concentration on a spell during their Trance variant of a rest, but I cannot find the source on that right now. 

If you want to see Crawford's responses on this question, you can go here https://www.sageadvice.eu/can-an-elf-concentrate-on-a-spell-while-meditating/

Crawford's referring to the fact that the PHB explicitly states the things that can break concentration:

• Casting another spell that requires concentration. You lose concentration on a spell if you cast another spell that requires concentration. You can’t concentrate on two spells at once.
• Taking damage. Whenever you take damage while you are concentrating on a spell, you must make a Constitution saving throw to maintain your concentration. The DC equals 10 or half the damage you take, whichever number is higher. If you take damage from multiple sources, such as an arrow and a dragon’s breath, you make a separate saving throw for each source of damage.
• Being incapacitated or killed. You lose concentration on a spell if you are incapacitated or if you die.

His reasoning is that since Trance doesn't impose the Incapacitated condition(the way being asleep does), they can still maintain Concentration on a spell during their Trance. Which might seem like a big advantage except there are only a handful of Concentration spells with durations of more than an hour.