Use a clock timer in order to wait
See waiting and timing in part II of the FAQ
There is also a "break" block in the Control section of the blocks editor to help you break out of a loop, based upon conditions
From what you say, start the loop, break (record position of break in loop), start the clock, continue the loop in the clock timer (call another procedure with same blocks, using the break point as the starting point)
Or whatever you intend....