I have just stumbled across this thread. I'll try to phone GdS. I've done loads of these, about seven or eight depending on how you count them, several on foot and a few by bike. Things are different in the time of covid, during which i have walked the French Camino twice. Have also taken the boat to Santander then ridden through the Picos de Europa thence along the Frances. GdS won't be riding any Caminos in November, December or January unless he's gone mad. For others: getting the bike back from SdC is dead easy, just take it to the post office and put it in a box they give you, stick all your kit in as well, and it'll arrive at your front door in about four or five days while you fly home with a small bag of hand luggage. Cost about €90.
Going out: If you have to start from Santander you can fly from Stansted and if you don't like the bike on the aircraft you can pay someone to send it in a van. The price of sending it in the hold is about £30 to £60 i think, plus the pain of getting it to the airport. Many places to stay are now closed, perhaps forever, and the dormitory accommodation is now by law reduced to 50 per cent capacity while the number of walkers is almost at levels of a normal pre covid year. You must, must, book ahead by about five nights or you'll be sleeping in the church porch.
Only municipal albergues have the rule that cyclists wait and get the last bunk: I've never actually seen it enforced.
If anyone wants more info, DM me.
HTH