question about combat waves

Concerning waves: does it matter when you attack? I mean, if there are 2 waves needed, will the results be the same when you first attack with 1 wave and then wait for a day or so to gather new recruits and then perform wave 2, or do you have to use 2 generals and attack with both waves at once?

I doesn't matter if there is 3 minutes or 1 day between. I am not sure, if it still doesn't matter if there is 5 seconds between, but normally I wait for the first battle to finish, before the next general arrive. Perhaps the word "wave" is misleading, since it doesn't have to come as waves. 1st and 2nd battle is more describing, since the enemies don't respawn.

thanks!