Yeah, I looked into it a bit yesterday and put up a post: GL-S20 TREL support - #2 by judahrand
Probably best to put any details there? 
Very exciting! I was going to say that it would make it pretty much the best value Thread Border Router (especially given that it is PoE) around but the price seems to have increased by almost 50% (£43 -> £66) since I bought it 
! Still a great product but a bit closer to the Aqara Smart Hub M3 which has Thread and PoE but also has Zigbee for an extra <£30. I guess if you guys keep the speedy support and updates coming there is a value add in that though! Will hold my breathe for TREL!