Sabrina
Here is another option you may not have considered: make the whole camino experience last a whole lot longer and cycle from home - in annual leave-size chunks over as many years as it takes. (Or start somewhere in Holland, Belgium or France).
We are cyclists and I have a full-time job with only ordinary length holidays. So far we have
1. cycled from home (near Ely) to Harwich over a weekend in July 2007
2. cycled from the Stena line ferry at Hook of Holland to Rheims in Sept 2007
3. cycled from Rheims to just south of Limoges (on the Vezalay route) in Sept/Oct 2008.
Each trip has had its own flavour and excitement, and each one has built on the previous -
so the first was just dipping our toes on the water, the second was about discovering that we could trust that we would somehow find somewhere to sleep each night, and that even bad french is good for communicating, and the third began to be more about being part of the pilgrimage, and improving the french! Our blog (see below) will give you a flavour, even though last year's bit is not complete yet! (As I said, I do work full time!)
Another advantage is that we have built up our experience in travelling to the Camino (Jakobspilgrimspad or Chemin de St Jacques) - from having to put our bikes on the train from Harwich and then begging to be allowed to put them in the boot of the bus replacement service (avoid sundays), to booking our route home from Reims at Reims station, to cycling across London from Victoria to Finsbury Park without a very clear idea of where Finsbury PArk actually is, above ground, to travelling on Eurostar last Sept, 4 days after the fire in the tunnel, and returning from Limoges and cycling/pushing bikes across Paris. So far, no flying, which always sounds very difficult with bikes.
And returning to Reims this year was fun - we knew which way to go to the youth hostel, and the receptionist remembered us and welcomed us!
NB I would agree with Johnnie that 500km in 10 days is probably about right, if you are not speedsters but likely to stop to look at places and walk up a few hills. We often do more than 50 km a day, but reckon on a rest day somewhere interesting after 3 or 4 days moving on. So far we have not had a fixed idea of how far we were going to get, just which towns or cities have main line rail stations.