Could be fuel related. But it seems odd that it would be fine (did a 7krpm pull) without issue when it was just below its normal operating temp on the gauge(I know, I know, just wanted to test).
i also find if I sit in traffic for a while on a hot day, the rpm at which it starts acting up drops significantly. Like the one day I was in stop and go and it was doing it at around 3000rpm. Almost like something is getting heaksoaked. It feels like weak soark/coils but i’ve tried two sets of coils and plugs lol