Oh, I'm with you on the permit thing, we just missed the change too.
Incidentally, when your wife changes her driving licence, would she like to keep all the additional categories for driving larger vans, minibuses, etc? If she just does the standard 'eye test, fill in a form' thing, she'll only receive a licence with a category for cars. I did a post about this on the Sticky thread about changing licences:
[Drivers licence] Conversion and questions
(Not sure how that link will paste, my post's about halfway down page 18)
It's not terribly complicated, just a few more admin hoops to jump through, but otherwise when you go back to the UK she may find she's lost those categories for ever - the DVLA hasn't given them out automatically with new licences since about the mid-1990s.
kodokan