It is the Asia/Taiwan Dual SIM Variant. htc_imedugl: 2Q5510000, CID: HTC__621, version-main: 2.47.709.1. (after latest OTA to Version 2.50-709.3 within the OS).
I'm in Los Angeles, so I am not overseas. Which FW versions do you think I should flash to be able to get one of these ROMs working?
I am desperate here as this is my everyday phone and my HTC10 has the notorious battery problem. So, will the latest .401 DUGL Firmware work fine to be able to flash this ROM and have VoLTE/IMS etc. working?
THANKS SO MUCH FOR YOUR HELP!!!!!!!!!!!!!!!!!!!!!!!!
**UPDATE** -- So, your instructions worked perfectly, though it was not too easy to find the HTC_DevInfo_Tool, but I found it and changed the CID to match the .401 RUU now. I flashed HTC_Europe_2.55.401.1 as you suggested and everything works, INCLUDING being able to install this LeeDroid ROM, except for VoLTE/IMS/WiFi Calling etc. as you also previously mentioned on these .401 versions.
I found a fix in this thread here and applied the edits to the files: https://forum.xda-developers.com/showpost.php?p=78252551&postcount=1
So VoLTE/WiFi Calling/IMS are registered when I go to the dialer and input the MMI code *#*#4636#*#* and then look at the IMS Registration.
The 4G icon at the network signal bars only displays 4G, but I found the LeeDroid Tweak to make that display LTE and also for VoLTE to display. The only place I notice that the Network Type says "4G" only Settings>System>About Phone>Network "Mobile Network Type: 4G".
So my question is, did I just tweak the GUIs within the ROM to just display LTE, or am I REALLY on VoLTE/IMS?
I attached screenshots of how everything I described looks!
I'm VERY curious to see what your opinion is!