I have my cake layers baked and frozen in my freezer right now.  They are not levelled.  I need to decorate the cake on Friday.  Should I take the cake out of the freezer on Thursday evening and leave it on the counter to thaw overnight to level on Friday am?  Thaw in the refrigerator overnight and then level?  Or just take out a couple of hours earlier on Friday am and then level the still partially frozen cake?  In Southern Ontario so it is still relatively cold here-no heat/humidity to worry about.

Cakes do not take very long to defrost so you would be fine removing them from the freezer in the morning.  But nothing wrong with leaving them wrapped on the counter overnight either.  Comes down to personal preference.

My preferred method is to thaw in frig overnight   It’s Up to you which way to go :)   

mine is to ice frozen already filled cakes -- no wrong way

Like kakeladi, I generally thaw in the fridge overnight, but I have let them set on the counter for a hour or so.