Suppose a Level 6 Warlock has expended both of their Level 3 Spell Slots. Then, upon receiving XP, they gain enough to level up to Level 7. They immediately gain access to their new spell (and their replacement spell if they so choose), but what happens to their spell slots?
- They now have 2 4th Level Spell slots, ready to be used, and their expended 3rd level spell slots vanish
- They now have 2 expended 4th Level Spell Slots, and they cannot be used until they take a Short Rest
Which is it?
Best Answer
They are the same slots so they remain expended
The Pact Magic feature works a bit differently than Spellcasting. You don't gain two higher level slots and lose your old ones. The feature says (emphasis mine):
So, you have two spell slots, and the table describes that their level moves from 3 to 4 when you reach seventh level. Therefore, those slots increase in level when you level up. These expended 3rd-level spell slots are now expended 4th-level spell slots.