Wut? I don't understand. What is QTC and why XP-L?
Dunno, but for my tail amps measurements, I remove the tail, then for lumens testings, I re-assemble the tailcap on the light. It's a difference, and maybe the cells differ in handle the resistance change: DMM vs. tailcap (with spring bypass of course). Again, my tests are not on a bench with a bench PS or anything.
It's all a big guess until HKJ tests them, I've always found his internal resistance results seem to match up with my own "in light" test results, so more waiting til he gets them in.
Edit - I see he ordered them here: https://budgetlightforum.com/t/-/34262