R25 (so helpfully quoted above by holbrook) uses the passive tense (may only be charged to a maximum of 100 psi). I would read that to mean that if at any point the charge in the reservoir exceeds 100 psi, the rule has been violated.
If the tank is filled with air at a temperature of -65 F to a pressure of 100 psi and then raised to a temperature of 70 F, the pressure in the tank will rise to about 140 psi. I suspect this would be considered a violation of R25.
Additionally, I suspect the very conspicuous condensation and/or frost on the tank would be a hint to the officials to look closer.
For the curious, for pressures in PSI and temperatures in F, the equation for pressure change is:
((P1 + 14.7) * (T1 + 459.67)) = ((P2 + 14.7) * (T2 + 459.67))
14.7 psi is generally considered atmospheric pressure at sea level.
459.67 is the difference between 0F and absolute zero ( see https://en.wikipedia.org/wiki/Rankine_scale)