Fingers crossed. Job done.
The BT essential unit has been carried about to wherever I happen to be but, today, a cheapo *phone outlet to phone outlet cable* arrived. Plugged in to the router and the *outlet* of the BT copper wire box and the Panasonic set up is restored.
I cocked up the internal re-wiring:-(
Faceplate off and incoming pair snipped, I lifted the securing latch and both tails dropped out before I had noted the colours/positions!
Any unwelcome consequences? Also any thoughts about filters as I have collected lots over the years.
Curiously, the blue light from the router has disappeared.
Thanks to all who held my hand:-)