Wow ! Got through to MPD on about the 20th attempt today.
The poor lass was very good, and explained it's Vodafone holding things up (apparently) and things should progress tomorrow (fingers crossed !).
She also said they were very busy, but when I asked if there was a better contact method for them ('such as ringing the store direct') she said no, this number was best.

Oh well. At least it's something !