So the collector goes to the 24V voltage & the emitter goes to the relay & D2 junction, thats what the schematic says?
The PCB I received has the T4 "half moon" shape around the wrong way so the PN222 needs to be upside down, collector towards the 24V voltage / mic i/o side of the board.
The layout link posted at the start of the thread also has the T4 shape around the wrong way but the EBC appears to be the right way around as per the schematic. The collector is towards the top of the PCB / mic i/o going to the 24VDC voltage & the emitter goes to the D2 & relay junction. So the PN222 goes upside down compared to the T4 "half moon" shape!
I had an old layout saved which had the EBC opposite to the layout linked at the start of the thread which has confused me even further see my previous post (& attached file