enchanced levels of cross class abilities

Simple question that I cannot find a factual answer for:

I use internal release as a cross class ability on my Warrior and it is 20% crits below lvl 36 (MNK/PUG). If I lvl MNK/PUG to 36, will I gain the enhanced rating of 30% crits on my Warrior?

This applies to many other cross class abilities, such as Convalescence and Featherfoot.

I would like to know before I waste time levelling.

Thanks very much.

Nope.
Traits are not cross class.
So you gain the non-upgraded version of the ability.