Yes Macca, I’ve seen this before in October when Brexit was supposed to happen on 31/10.
The AP on our XC40 went down drastically from £3500 to £1999 in Q4 but with the qualifying phrase “offer available from 01/10/19 to 31/10/19”. It was of course maintained beyond that when Brexit was postponed.
In your shoes I wouldn’t be taking too long to decide as with the popularity of the XC40, I can see the AP rising to pre Q4 levels.