Having wet dreams in the first hours of sleep (before dream sleep)

I've been on nofap for 9ish months now. The first 110 days of which were hard mode without a relapse. In this period I had wet dreams on average every 5 days generally following a sexual dream. Obviously at some point I gave up and started doing occasional M to prevent these wet dreams. To this day I haven't relapsed and I try do M once a week.

However, I still want to find out if semen retention is actually noticable if you can manage to do it. I went to youtube and found a really good video that focused both on lifestyle changes and concrete nightly actions to prevent wet dreams. This included:

Lifestyle changes:
- When feeling urges do some deep breathing to 'transmute the sexual energy'
- when masturbating, focus on pleasure instead of ejaculation (at least 20 minutes)
- no porn (obviously)
- direct your energy with intention/attempt all day awareness

Practical things:
- sleep on your back
- no tech at least 90 min before bed
- stretch legs before bed
- deep breathing practice/meditation before bed

I've also been taking cold showers daily, avoiding all sexual content and trying to keep urges/images to an absolute minimum. I've been doing all this religiously for about a month but only 9 days ago I decided to really try out no M for longer than a week to see if it works.

I really was convinced that it would work, but tonight I woke up about 1.5 hours after going to sleep and that hope was gone. I don't think I even entered REM/dream sleep yet and didn't even know it was possible to have a wet dream in that part of sleep. I'm afraid if this didn't work, nothing will. I'm hoping someone can offer me some final piece of advice before I give up on semen retention for good. (I'm actually pretty satisfied with where I am in rebooting, just would like to see if semen retention has an actual effect.)