I don’t think either of the teensy tools supports specifying the port to use (teensy-cli certainly doesn’t document it anyway)… and that led to some … interesting… results in another thread when multiple boards were connected…
I just came across this mini suite of tools again… looks like it supports Linux, Mac and Windows, and can reset / upload / monitor by port, serial number, board type… will have to see how to go about using that instead! 