It's a bit early in the game to be making any major judgement calls. I agree it would be helpful to get some numbers in the evening cycle and getting a test before bed is always a good idea so you sleep better and don't have any surprises. My first thought it that Chester has bounced and may just be coming out of it. I'd hold the dose until tomorrow, try to get at least a +2 or +3 reading in the evening cycle and then have a look at it tomorrow. The more data you get the easier it is to start seeing patterns and that is how you make dosing determinations.
Chester is getting some pretty wide spread on his numbers. The 9.7 and then back up to 21.5 on the 9th looks like a bounce. The AMPS of 6.8 and PMPS of 28 on the 10th makes me wonder just how low Chester might have gone in the cycle.
I would not recommend shooting a full dose on any pre-shot reading under 11mmol until you get a lot more data. So I stick with 1u for now? Sorry - still getting used to the terminology
If you get a pre-shot reading of less than 11 mmol,
stall (?)without feeding and retest in 15 to 20 minutes to see if his BG is rising or not. You can
stall any number of times (?) but doing so will impact your shot times and may not be practical if you are working or have to go out for any other reason. If stalling is going to cause a problem time wise for future shots, better to just skip than shoot too low a BG as long as Chester doesn't have a history of DKA. If he does have a history of ketones or DKA, then I would post for assistance as it might be better to consider a reduced dose shot.
Because Chester was a stray, there is very little history on him
To convert UK readings to US readings simply multiply the UK reading by 18.
No I don't think you need to be worried right now.
Just make sure you don't shoot that low just yet.