Took a break off editing, came back to the C10 and it had gone offline again mad

This time all that was done was to change the port on the router and hey presto, it came back on line again. No re-boot of either the C10 or TwinStore.

So it is definitely not a power supply problem and appears that T3 is the culprit as suspected (T1 & T2 are powered off) so it is a network problem as suggested earlier.