So went to bed at 23:00hrs but ate my last meal at about 22:15hrs
Didn’t have my usual Keto coffee this morning and had a black coffee with Stevia at 12 noon.
I had three coffee’s in the time till my first meal tonight at 19:00hrs. So thought I had done a 20 hour intermittent fast. Apparently Stevia breaks a fast 
so only 14 hours I did have a proper metal taste in my mouth though all afternoon, which I thought indicated I was back into Keto.
Thoughts?
Looks like a 20-hour fast to me. Not sure why Stevia would break a fast (if you were gunning for a weight loss fast). Congrats!
According to Dr Fung in the Obesity Code most artificial sweeteners stimulate insulin production. When you have spikes of insulin your body will store fat and not lose weight.
After reading that recently I stopped all use of these aids. I was only using Stevia maybe 3 times a month and 1/2 diet coke once a month.
I think I’m lucky I don’t crave sweats like the rest of my family does.
If you stop burning ketones and have them in your blood, maybe you will start to taste them. I do taste metallic when I know I’m in ketosis (IF, EF, extremely low carb day).
I didn’t feel at all hungry yesterday, so I am going to push on today again with no food for the day and eat later on tonight.
Thursday night I was 16stone 8lbs. This morning when I got up, and got on the scales I was 16stone 4lbs.
Results like this keep pushing me on.
It is always nice to see lower scale weight (if that is what you are looking for).
But, it is likely mostly water weight - with (due to IF and good keto) up to a pound of fat depending on your overall size and how much you have to lose.
I am not trying to downplay - I am just throwing my usual warning out there - a getaway weekend, a party, an extravagant meal with friends etc. might bring some (or all) of this water weight back. The point is, down’t get down about it - just know that gain is as natural as this seemingly large jump down.
Daily scale fluctuations, especially around dramatic dietary changes can drive you crazy (because your body will hold on to different amounts of water under different schemes). In fact, given this drop - you may want to look into whether you should be having some salt in the morning - better to be “not tired” at lunchtime than to have coffee at noon (as you get older - it seems caffeine absorption slows and the 6-hour half-life turns into 10 or 12, leaving too much in your system at bedtime).
Best to measure the same day each week under similar conditions (same diet the whole week and first thing in the morning after the bathroom and before any liquids for example).