Im just trying to slowly wean him off nappies so it’s only weekend and at night I put it on to give him a break from toilet training which he does weekday nights. I know everyone gets there at their own rate toilet training, but just asking if there a strategy that works for boys at night that helps guide them to wake up and know to go to the toilet themself instead of wetting the bed would be good.

We used the Bed Wetting Enuresis Alarm Success Package from the parenting garden.com.au with great success. It clips onto their undies and a band around their arm. They have to manage it themselves, change themselves etc. All part of the process. It worked within the 14 days as recommended. He did have an odd accident a few months later but all is still good. When wetting s detected it sounds an alarm, flashes a light and vibrates on their arm. (Still slept through at first lol).

I take it that you have spoken to your local GP about this and have rules out any medical issue?
If you have then as hard as it is just dont stress over it. Im not sure why you only put him in night nappies on the weekend? Perhaps do this every night. He will get there in time.