Well....after a long wait and getting sent a new unit of the same 'older' model from both the dealer I originally bought it from and Garmin, I finally received the Cap screen replacement yesterday.
Had it working yesterday in the house, all seemed good. Screen is quick to respond to touch. Works with gloved finger.
Only difference to the 'about' screen is that the software version has gone up from 10.3 to 10.4
The box date range has changed to 14/2024 - 14 2-26, as pointed out by tspivey, week 14 would be the week from 25th March 2024
Garmin have stock of the cap screens come in and go straight out
The BMW part number on the box does relate to the Nav6 on a small number of european sites but appears no longer in stock and, to my suprise, a Samsung series 7 oven with self closing door. Google is weird.
Looking on a US BMW forum, they were on page 124 on this subject. Also started getting cap screen early January. I imagine this is going on all over.
I shall be giving it some stick over the coming weeks, starting today, as unusally, it appears not to be raining and dry.
On the upside, I now have 3 brand new Nav batteries as they didn't want the batteries back.
And the dealer network is updated, Chester Motarrad is now in there.