Definitely only worth delaying delivery for imminent new plate. There'll be maybe £250 between Dec 13 and Jan 14 registration come trade in time, but £750 - 1000 between Feb 14 (63) and March 14 (14) due to the impact of the new plate. My p/xed Scirocco slid £850 between Aug and Sept 13, but only approx £230 per month for the preceding 3 months.
Nov availability? Pick it up ASAP, you'll see no advantage in delaying pick up by a month or 2.