Just to update. Decided to see if I was a mouth breather in the night and to see if that was causing it. Did some googling and came up with mouth taping which is a proper technique. **Please do your own research into this before attempting to tape your mouth**. It was ok for me and I didn't wake up once in the night with a dry mouth. I now have a cheap makeup headband which I wear as a diy snoring chin strap. It isn't over tight but seems to remind me to breathe through my nose. Have also taken on board about electrolytes as am low carb. Wanted as simple and clean as possible so to a 2 litre bottle of water I add 1/4 tsp fine himalayan salt, 1/4 tsp low sodium salt (they add potassium to make up for the sodium which is good for this) and 1/2 tsp of epsom salts. It's actually quite nice once you get used to it. Really needed to get back to sleeping so thanks for all the advice.