Dry and cool this morning, so looked at the patient.
The coolant level had dropped from just under Full to just under Low in 30 miles from Zuffenhaus, so leaking.
NS front wheel off and the hose I replaced looked dry but a VERY slight weep, so off it came, catching nearly all the coolant for later use.
Last time round, (4 months) I bought 2 oversized, correct ID O rings and decided to fit one instead of the skinny by comparison ring that came with the hose.
With some rubber grease, the hose was replaced, the new ring being a very satisfying snug fit, and a new clip too!
Strained the drained fluid, back in the car and started it up, the fluid level being bang on Max.
Heater wide open, fans on and after what seemed a very long time the hose became luke as best warm.
Dry so far, so took it for a high revving run (I had burped the system, though could not say if any air came out).
It is now cooling down, the hoses at the front are all very hot to the touch so I imagine the system has fully flowed around the car.
Will top things up when cold tomorrow morning and see if any drips under the front (besides me).
If this fails, it is the Full Monte.