ADD me to the Quire… If SEEED would dedicate some real effort in getting this together half as good as the Adafruit stuff. Great link, lots of good knowledge there.
I’ve used their libraries by accident and it worked first time out. trying to get the best of both worlds with the seeed stuff is a struggle if at all possible.
my .02
I love the seeed foootprint and basic premise of the BLE Xiao.
The Sense version raises the bar, unfortunately they don’t reach it with the firmware support.
They should run at it again but add the RTC. talk about a complete package… WOW 
HTH
GL :-p