Thanks everyone I'll get DH to try This Works sleep spray. When he finished his teaching career he took a part time driving job for Royal Mail which involved getting up at 3am and he believes his brain is still geared up to getting up at this unearthly hour. He's getting sufficient sleep but would prefer not to have this nightly interruption. Fingers crossed it works!
Do you feel guilty if you have a lie in??


I'm not sure I buy it myself, but if you suggest it to him it might make him feel better, and after he's checked the locks and seen that everything's switched off, he can get back to bed and go to sleep straight away. 

Currently using a CBD oil, no success with that either. 