As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW RECEIVED A BLEED 1 OVERPRESSURE CAUTION MESSAGE AFTER TAKEOFF THAT WOULD NOT CLEAR. DECLARED EMERGENCY, RETURNED TO FIELD. C/W FIM PROCEDURES. FOUND THAT PACK 1 WAS PREVIOUSLY DEFERRED IAW THE FIM, ALL FAULTS CLEARED AND OPS NORMAL.