Darn it, oh well. Now the decision, take it in January or wait until March??
I may have posted before that in my opinion, I wouldn't wait a further 3 months to take delivery of a car that was built in October, that mean's it will have been waiting around stagnate doing nothing but rusting for 6 months. For me, it's not worth the few extra hundred £ that it will be worth come trade in just to be driving around with the latest plate for 6 months before its replaced by 69. Besides, my dealer has told me they will honour the trade in value of my current car which was based on October trade in values as it is VW's fault, I can imagine the few hundred pound i'd gain going to the new plate would be offset by the revised value of my current car in March 19.
As soon as it's ready I'm having it!
Good point well made 
Also, once it’s delivered to the dealer, if it’s sitting there for three months at the dealer’s, there’s a risk of it getting scratched / dinged, or used as target practice by the local pigeons and our other feathered friends. The dealer might even put it in the showroom as a display model, when it’ll be at the mercy of Joe Public and their kids crawling all over it.
Unless the dealer has secure indoor storage facilities that can’t be accessed by customers I’d take delivery in January.