Monster Flip Flops Yugioh - Need Some Clarification On Monster Effects?

Yugioh - Need some Clarification on monster effects? - monster flip flops

Flip Flop Frog:

Once per turn, turn them face down in defense position. When this card is turned face up, you can control your opponents monsters to his hand back control of its owner, until the number of face-up "Frog" monsters, except "Frog the Jam".

He says once per shift. Can it revolves around the attack and then again on the head, while a trip?