Just found this morning I can get a one-way car rental from home to Dover (including excess waiver) for £100. That's for something like a Ford Focus. So with a flight back from Nice with Jet2 for under £150, including a big bag and bike, the two together are less than the bike bus. Those arrangements seem to suit someone who worries like me. (I had wondered about the train but it would need at least two changes from home.) It'll get me to Calais for early evening and I'll treat myself to a hotel for the night before starting the ride next day. Unlike with the bike bus I can choose the day I go and the day I return. With the benefit of hindsight, my target of 35 miles per day suited me perfectly. I never suffered any aches or pains cos I had a rest every afternoon, having arrived at my chosen campsite by around 4pm at the latest on most days.
From feeling quite negative yesterday, i can now feel a plan coming together. I can even cope with stripping the bike down if I don't get a positive response from Jet2.
Just need a route. I need to try to absorb some of the info on that from contributors here so far. I do have an up to date Michelin road atlas so that helps with planning at home.
Thanks to all who've replied so far and, as ever, I'm open to any further advice.
Cheers all,
Geoff