Tyre pressure increases with temperature and not speed (unless running from cold first time). The rule of thumb is 1 psi increase with each 10 deg F. The most variation that I have seen on 30 psi is about 2 psi increase on a hot summer day. Racing drivers usually work the tyres to soften the rubber for grip. I am surprised that the fitter did not inspect the rims during a final balance or that a tyre can remain inflated above 10 psi without proper seating on the wheel rim.
