Inspired by talk on another thread about the possibility of the Harlandic loco having been newly painted in NIR maroon before its withdrawal, and pics on IRM a couple of years ago of a 141 in "freight" silver and black, what passes for my mind began wandering into "might have been liveries"...
There are many examples of where a new livery was never applied to old stock about to be withdrawn, but ran concurrently with it.
An E class in "supertrain" livery
An NIR AEC set in maroon and blue; likewise an MED.
Being political: a Hunslet in black & tan when the "troubles" produced a United Ireland, or to be balanced, a 141 and laminates in NIR maroon/blue after the 26 counties rejoined the north in the UK!
Steam lasts - a "jeep" in NIR loco maroon! And a few remaining J15s plus Maedb in CIE black'n'tan.
The West Clare survives another year. Walker railcar in black'n'tan, F class diesel in all-black?
And so on.......