From page 207 of the MM,
A character who becomes a lycanthrope retains his or her statistics except as specified by lycanthrope type. [...]
For example:
Werewolf. The character gains a Strength of 15 if his or her score isn't already higher, [...]
If some PC had a Strength less than 15, and gained a Strength of 15 this way, would they retain the 15 Strength if the curse was then removed by e.g. Remove Curse?
The other properties clearly seem to be removed, at least RAI, so I would expect this one to be as well, but I'm just requesting clarification, since changing an attribute is a little different to gaining traits.
There is also the more complicated case of taking an ASI while afflicted by the curse:
Assume a PC has a base Strength of 12. They become a werewolf, so they gain a Strength of 15, then they level up from 3rd to 4th level, and increase their Strength by 2 points.
- Is their Strength now 17?
- Does it remain at 15 because \$12 + 2 = 14\$ and \$14 < 15\$?
- If their curse was then removed, would they have a Strength of 12, 14 or 17?