From the target in OP there's 3 different POIs.
1. the very first shot
2. the following 3 shots, and the "4th group cold barrel"
3. the "3rd group"
POI #2 has 6 shots within an inch or so. POI #3 has 5 shots within an inch or so, and is a bit higher than POI #2 but is also shot from quite warm barrel.
After checking the rifle, scope and shooter as advised, I would work on that. Fire first shot on separate target, and then test for "coldish barrel group" wait few minutes and test for "warmish barrel group".
Yup. Totally agree with this. The more I look at that, the more I see very little evidence of anything really wrong. I will put money it being a barrel that needs a good fouling after a deep clean, plus some shooter frustration. Possibly some issues to do with shifting hold/cheek weld etc.
