I can remember it being reduced to a single 175/1, but how was the Llandudno Junction to Llandudno (and subsequent journeys) covered? In normal circumstances the trailing 175/0 is scheduled to drop off at LLJ.
There's a similar obvious question about the 0852 Picc-Holyhead, which is scheduled to drop the trailing unit at Chester, which then follows as a stopping service to Llandudno. I'm sure the 0852 was running as a 2-car unit for a time. Of course, it couldn't be reduced to a 3-car 175/1, since the leading unit needs to be a 158, it finishes up on the Cambrian later in the day.