Swap HV battery on Gen 1

This is my first attempt to repair a gen 1 prius. I am pretty familiar with gen 2 hv battery repairs and have been successful with those in the past.

Here are my questions: I come across mention of giving the vehicle 30 minutes with ignition on and no engine start to allow the HV ECU and the immobilizer to "get acquainted." Do I need to do that when I swap in a replacement battery on a gen 1? I haven't come across this before and my swap failed with a P3030 code. I am planning to pull the lid off the battery and do continuity testing on the sensing harness, look at the ECU plug for corrosion or signs of burnout. I think this is probably a simple break or fracture in one of the 22 gauge sensor wires, but ran in to the discussion of the 30 minute "get acquainted" period and I want to know more about that before I proceed.

I have another gen 1 pack all charged and ready to swap in, but if I can fix the problem with a harness replacement in the car, I would save some heavy lifting and my back would appreciate that.

Thanks in advance,

Mike