The updated Guidance that we are discussing has not yet been published, on BANA's website or elsewhere.
Confession: I, too, have been following the updates covered in the webinar we are discussing.
Disclaimer: If your note on the Transcriber's Notes page says, "This volume has been transcribed according to The Nemeth Braille Code for Mathematics and Science Notation, 1972 Revision, 2007-2015 updates and the Guidance for Transcription Using the Nemeth Code within UEB Contexts .", then that does not include the batch of changes/updates that includes the note to only include abbreviated units of measure in switch indicators with a modified number or other technical expression.
If you are applying that batch of changes, then perhaps a more thorough note is called for.
Technically, the only official BANA guidance we have is what is published.
I'm afraid that is all the input I have at this point.