APC UPS Battery Backup Firmware Update Process

Download the .exe 7.1.6 file from APC and use unzip name.exe on the file to get its files. https://www.se.com/us/en/product/AP9630/apc-ups-network-management-card-2/
If using a Windows computer or VM, just run the EXE and it will automatically do all steps of the firmware process after you put in the IP, username, and password
Otherwise, use FTP to update https://www.apc.com/us/en/faqs/FA156047/#FTP (don't use https://www.apc.com/us/en/faqs/FAQ000242942/)
ftp ftp://apc:apc@x.x.x.x to connect with user APC and password APC
Then bin to enter binary mode and then put apc_hw05_bootmon_109.bin. Once it uploads, disconnect with exit and/or CTRL+C and reconnect after a couple minutes
Repeat this process twice more, firstly for put apc_hw05_aos_716.bin first, then put apc_hw05_sumx_716.bin
Modify the preconfigured config file. Update the naming everywhere else by find-and-replacing the Network Number (NN) and other similar descriptions. The MAC address can be safely ignored. Then go to Configuration/General/User Config File, pick the nn2299-roof-apc-nmc2-config.ini and apply it. Then reboot the NMC using Control/Network/Reboot to permanently apply the settings.

These are updated way more rarely.
Thankfully, this can be done easily through the NMC2's web UI under Configuration → Firmware upgrade. Pick the file and wait 5-10 minutes for the upgrade to ~~complete~~complete. On older NMC2 software versions (6.x.x and earlier) the option may not be available. In that case, update the NMC2 and then update the UPS
Download the UPS firmware ZIP and find the relevant file inside. For example, a UPS with ID18 and model SMT750RM2U is going to need SMT18UPS_15-0.enc as per the reference table in the FAQ https://www.apc.com/us/en/faqs/FA170679/. First turn off the outlet group, which cannot be on while it's updating.