The first tube had sealant in which slowed the rate of deflation. The second tube didn’t and leaked air so that my pump could get it to around 10psi and no more. On the way home yesterday and today I was regretting not having sealant in the third tube.
I retained the original tyre and it is a tubeless one so it just needs two holes plugging and it will be fine - I have them marked already so I will order in some mushroom plugs and repair the tyre ready for refitting. The new tyre is also tubeless so that can sit in stock for when the original is worn out.
Oh, if anyone is interested the roads in the Dordogne are breathtaking good - up to the second flat I had a run of 250 miles of sweeping curves, villages, cracking views, forests etc. stunning riding to the extent of I am going again next year but having a few days in the area just riding. Plus the roads are in really good condition.