Another interesting battery test, not sure if it will be useful to anyone else but just incase: (TLDR seemingly more time out of 24v XLRs vs EXT for PIP mics, more testing to come)
Picked up this Dual XLR > 3.5mm phantom power converter (I couldn't discern solid consensus on if it was optimal to run DPA 406X's with 9v vs 5v PIP and want to play it safe - plus the mic inputs are rated at a higher max input, though it is a bit unlikely to ACTUALLY come into play..)
https://immersivesoundscapes.com/accessories/Adapter-for-PIP-mics-to-work-on-XLR-48V-Recorder-p492004466Set inputs to 24v phantom power, otherwise same settings as before wrt 5 seconds backlight and low contrast 32bit etc, Eneloop Pros
I had 7.5 hours left on my SD card and didn't expect it to make it this far given the ~8h of recording time on PIP. But it made it the full 7.5h and I was left with what appears to be a good amount of juice. Screenshot attached is battery meter after recording for 7.5h and running for 9h total (supplying power to mics the entire time!)
I will wipe my card and do a full length test but this is indicating that I'd actually get more time out of the converted phantom power mic inputs compared to EXT INPUT PIP?? That seems odd, right? Not that I'm complaining. I should be running these tests multiple times and averaging the results for proper analysis, too - wonder if my og PIP recording test could have been an outlier and if I'd get more time with repeated testing. Just seems so odd to get more time out of dual 24v.