GPS-RTK Dead Reckoning Bypass Calibration

Is there any way to bypass the calibration step? We have a couple of the GPS-RTK Dead Reckoning boards and we are getting frustrated with their calibration requirements.

We took one board on a long drive, and it seemed the calibration worked, but then it forgot the cal next time we powered it on. So, is there anyway to get the imu readings without calibrating? or without using RTK during calibration?

Additionally, the boards seem to struggle to get a GPS fix. I have mixed and matched the antennas between boards, but I can only count on 2/3 (not the exact same board every time) of them getting a lock. Even if the boards are right next to each other.