Originally Posted by
IAH-OIL-TRASH
It will be valid at either, but not both. I doubt it is a one-day pass. It is more likely a one-time pass and it will be considered used once you enter a lounge.
To maximize time in lounge, just head straight to C after arrival and use lounge there.
I guess the question for OP would be, which UC at EWR is more likely to deny entry to one-time pass holders, terminal A or C?