Could it be that the reason for all the “expedite your climb” and “expedite you descent” (since several versions) is simply that the AI/ATC does not know transition altitude or something like that (or it doesn’t always work or depends only on the difference between QNH and standard). I noticed this…

Transition altitude does not work?

arniex78 November 29, 2021, 2:10pm 5

I already know that my point was that it doesn’t work, at least not for AI traffic!