Defrosted fish- can I cook and then reheat?

[fruitcorner]

I have defrosted fish pie mix today and I am going to cook it now and make cheese sauce- can I then reheat tomorrow when I add the mashed potato and assemble the fish pie? Hope that makes sense

if the fish was uncooked when it was frozen and then defrosted then it is ok to cook the fish today and then reheat it once tomorrow.

great thanks very much!