Must a SB sized allin postflop bet be completed to the size of the BB?

[Rottersod]

I think he does have to make it the minimum bet but note that it is not considered a raise from SB and he will have action again if it is raised enough to allow him to repop.

Edited: Sorry, let me edit to make it clearer: It is a call and his action will be closed if any raise is not enough to repop.

Edited a 2nd time: Yeah, I didn't see it was post flop so I don't think it has to be a min bet.