Your comment below, I am not sure I agree with (sorry not sure how to quote just a bit):
However it's clear that I'm having to take far more Fiasp to reduce highs than I had to with NR. Just on this day I would have had to take about 20u of Fiasp to reduce the morning high without eating whereas with NR 12u would have been ideal.
Yes you did take 22u of fiasp but I don’t think that was ideal, as it not only reduced your blood sugar but it sent you hypo, and it covered 50g carb in the salad, plus whatever hypo treatment you used (I’m assuming you didn’t eat salad for a hypo but had fast acting carbs first). So a much lower dose of fiasp would theoretically have dropped your bg to a normal level. Stacking boluses an hour after each other is not advised as the correction will take up to four hours to finish working.
Sorry I wasn't clear. To deal with the hypo I had a salad that was a prawn/rice/mango/salad and it had 50g of carbs. So I didn't use any insulin at all and only food to treat the hypo. From 11.15 onwards I have taken no bolus whatsoever and if you look from 16.00hrs onwards I'm stable - this makes me think the basal is doing that. However I could be totally wrong!