First thing I'd do would be to remove the OPDA, re-pin it, set the engine to TDC, and re-install. That ensures the OPDA is in the correct orientation and just "makes sure" its right. THEN re-learn if you need to.
That kind of seems unnecessary if they're able to read where they are at off the ODB-II reader, especially with Blaine's context of the computer being able to adjust +/-10°.