Of course there is potential for further confusion when one considers that mil ac undertaking certain activities, or in height blocks encompassing the TA, operate the Regional QNH (RPS) well above the transition altitude, and are only required to set the SAS at and above FL245.
This must seem odd to some of our civilian colleagues when a controller asks to coordinate not above, say, 22,500ft on an RPS of 1038 against traffic at FL 230.
BA