I’m curious, what issues have you run into using the newest tool on older firmware? As far as I knew, the only remaining bug was during remote setup, which has now been fixed.
I was under the impression that all the important bits like detection results and current limits were calculated based on the firmware present on the ESC, not the version of the tool running.
While Vedder does actively push for folks to run the latest firmware, he has also advertised full backwards compatibility in the latest tool versions, and that is his reasoning for only allowing that version of the tool to be distributed.