If XDA is on it, I'm sure Essential is aware, but despite that you should let them know asap! I am 100% sure they would hate for this information to travel past the "enthusiast" they have been relentless with updating that device.
Is RF really bad on the essential? I've been contemplating buying this or the LG G6 (Both free for me stop the moment). I'm leaning on Essential due to it being unlocked and supporting more LTE bands. But if the radio performance is bad, then I may just wait until the Essential PH-2 is released (that is if the company doesn't go under). LG G6 is starting to seem more outdated as each day passes by and the bootlooping mess of their older phones turns me off.