Waking in the Middle of the Night

This seems unrelated, but it is in my efforts to attain lucidity, so I guess it fits here.

So I've been trying to use the "CAN-WILD" method, so I need to set an alarm in my late REM periods. I've been having trouble tracking my own sleep, mostly due to the fact that I wake up in the middle of the night.

So when you wake up in the middle of the night, you just go back into where you were in the sleep cycle, right?

How long do you have to be awake for it NOT to go back into the part of the cycle you left off at.

I don't have a very well understanding of some of the aspects of sleep cycles, so please excuse me if this is a derp question.

Doesnt REM cycle happen every time you sleep, if that is the case, then you shouldnt worry about the sleep cycle, just get up for about 15-30 minutes and try it then.