The option to spend Notability to overcap your Watchful stat is now locked with “Impossible!” Other stats have not been locked yet. The new system of raising the cap is intended to be a full replacement for overcapping, and overcapping will cease to exist.
If your Watchful is already higher than 212, then it will remain so, subject to the usual degradation (like Nadir). My understanding is that the cap cap will eventually raise above 212 but that hasn’t been released yet.
Regardless of what your watchful cap is (200, 203, 206, or 212), if your watchful is below your current cap then you can raise it by playing Watchful challenges or any other regular way (e.g. spending Favors).