Can I WBTB multiple times in the morning?

So I had a quick question about WBTB. Usually when I try this I'll wake up after 5-6 hours of sleep and go back to bed after staying up for like 10-20 minutes. I've yet to become lucid doing this but I almost always have a dream of some kind, and if I go back to sleep again I'll usually have another dream.

My question is, could I theoretically wake up for WBTB, then as I'm going back to sleep set an alarm for like an hour or so later and try again in case I didn't go lucid that time? Is there a limit to how many times I could do this, aside from just until I'm unable to get more sleep?

They whole point of WBTB is to get yourself to go to sleep right at the start of a REM cycle so that you are more likely to get lucid, either through a WILD or a more aware mind upon entering REM sleep. You only have so many REM cycles each night, so there's not an unlimited number of times you could do this, but if you want to do multiple WBTBs you'll have to figure out when your REM cycles are, which includes the WBTB. The reason people pick 4-5 hours into their sleep is because this is an easily defined time and the REM cycle is at least a moderate length at this time (15-20 minutes). I suggest, if you want to give it a go, figuring out your REM cycles on a typical night, using this chart as a guideline. Keep in mind that everyone is different do your times will be a little bit off, but that's a good starting point.

Also, don't do this if it means you lose a large amount of sleep. One of the keys to being successful at lucid dreaming is consistency. Consistent sleep schedule is a given, along with full sleep, so don't let this inhibit your sleep. Other than that, good luck and let us know how it goes!

In my experience you don't need multiple WBTBs. After one, your mind is more active and ready. You can have multiple lucids after that. Last night i did WBTB and then had 2 lucids.