@Lesley25 I completely agree that 'comparison is the thief of joy' with regard to social media! I hope your new friends are lovely and supportive 
That's a great idea about the calendar @Blomme, thank you - we do have a family calendar but I don't think he takes much notice of it. I might sign back up to Twinkl and print out one that's far more visual, which would help him to explain more what he likes/ doesn't like as well.
@MagratLancre (love the username, by the way!) I know PIL feel we are 'pandering' to DTS1 when we make allowances for him but really it's only trying to make sure he doesn't have an enormous meltdown
again ... equally, FIL can be very judgemental when DTS1 doesn't 'behave' (especially at mealtimes!) so it's difficult to know what he expects us to do!
Oh yes, DTS1 has to have at least two hours' exercise a day @RestingStitchFace, otherwise he's frankly unbearable! And outside is definitely better than inside - he tends to get overwhelmed by soft play, disco lights etc.
Another few awful nights' sleep for DTS1 and he's edging closer to meltdown territory
he just cannot settle himself at bedtime, he can easily take an hour more than DTS2 to get to sleep, even when thoroughly exhausted. Then the next day he has massive bags under his eyes and is constantly on the verge of tantrums... I'm looking into melatonin at the moment as plenty of sleep makes such a difference to him. If anyone has experience of using it that would be much appreciated!