Have just seen something from a few weeks back where bbc one wales announced a programme with a bbc two wales ident on screen - so although the screen logo said bbc two wales , the announcement said now on bbc one wales
That's happened before when a programme has moved channel at short notice and the Director has copied and pasted the running order into the automation.
You'd think they'd sub in the generic "This is BBC Two" announcement in that situation, assuming there's no time to re-record the announcement or do it live.