PT, AFAIK it is not right to say the MPPT buck converter converts volts to amps and there is a conversion loss doing that. I think it is just power in and power out and there is a power loss on the way through due to the voltage transformation efficiency.
The amps you get afterwards are sort of a by-product by dividing that output power by Vbat. They didn't come from "extra volts"
The Tracer manual linked above says to account for panel Voc at ambient temp when matching for the controller Voc limit. I thought it was panel temp that mattered, not ambient. If you use ambient you will have extra safety margin I guess.
