Windor's Chronal Cogitation

You meditate and make minor changes in you past when you last prepared your spells. You can change the spells you have prepared of 1st level or lower for other spells from your spellbook or class spell list. You cannot change spells you have already used since your last long rest.

When you cast this spell at 2nd level or higher, you can change prepared spells equal to or lower than the level at which this spell was cast.