Generally speaking, if the skill is on a silver unit not named Gadoras, you don't have to worry about the skill changing.
If the skill is a on a Gold unit and has a number (Example: Increase Heal I like on Iris), you can be pretty sure it will change after CC (to II for Iris, which is considered a different skill)
If the skill has a special name with no number (Magic Shells on the Gold Zola, nearly all event platinum units, princesses, etc.) you can be pretty sure it won't change after CC.