That is very odd about the bubbles. I never had any bubble on mine and no bubbles on the pei hi temp plate. Maybe yours got messed up when it was installed at bambu. Maybe try removing it and putting the spare one on.
So on most filament it will say on there the recommended printing specs usually around 190c-215c and like 40mm a second- 60mm a second printing speed. That second part is the key, you’re not printing at 40mm a second, you’re printing around 250mm a second depending on the speed setting. So ignore the recommended temps on the filament. As we speak I am printing a wall holder for my filaments using polymaker pla pro and I am at 250mm a second speed and my temp is 232c. And it’s perfect.