if I change my 100% vote to 50%, I'm not being charged additional mana, but the curation rewards are reset, right?
This is my understanding.
Trying to think of an example where not resetting CR could be tricky:
If you change the 50% vote to -50%, you consume mana of a 50% downvote.
Here, would you want/deserve to keep your curation reward?
No. Only if weight > 0.