Setting effect to expire at start of target's turn

[rhollander10]

Shockwave, from Gods & Magic, applies flat-footed to the target but expires at the start of the target's turn. I can't figure out the correct duration/targeting/expenditure settings to get the flat-footed condition to be removed at the start of the target's turn. Can anyone suggest how to do this?

[MaxAstro]

Change the "initiative to adjust on" value to the target's initiative. I don't there is a way to do that automatically, though.