Monster Grade Question

So looked everywhere couldn't find anything about it or maybe I'm not looking hard enough :p.

Read the help and it says "The higher your monster's grade , the more it's stats will increase when leveling."

So my question is ...

Does that mean I should try and grade up a monster at the lowest level possible and level him/her from there to get maximum stat gain?

orrrrr

Can I just level my monster to max and then feed it a bunch of stuff to grade up and still get the same max stats?

u can just lvl it up and upgrade after

the stats are calculated by a base stats multiplicated with lvl