Hello! Just thought I'd post an update.
We went on holiday for 2 weeks and I couldn't handle the whole family making comments about how much DS was crying before going to sleep, (and suggestions that sleep time was now feared by him, hence the question in my last post) so I ended up feeding him to sleep for most of the time!
He did pop two teeth while we were there so that at least explains some of the crying! We are home now though, and he has responded so well to pupd (or more like just pd) - he is falling asleep on his own, even lying himself down which he has never managed before. We're on day 4 of pupd so not quite there yet, but it is looking very promising
I'm also moving him onto one sleep which seems to be helping! My ultimate goal is for him to fall asleep on his own without non-mantra crying, hopefully we get there!
Thank you for all the help and support!