Complete Electrical Shut Down At 55mph

Last Saturday, while cruising happily along at 55mph,the engine on my 2016 America LT EFI suddenly cut out. The speedo & rev counter stopped working & there were no warning lights illuminated.
During the day I had covered 80+ miles and everything was good, no misfires, stalling, hesitation or unusual engine noises.
As I coasted to a stop (from 55mph) I automatically switched on the left indicator and was surprised to see that it worked.
When stopped, I switched the ignition off and on... nothing, however the alarm could still be set / unset as normal with the fob & the indicators would flash in response.
The battery, a Motobatt AGM is only 5 months old and had been coupled to an Optimate charger / maintainer all of the previous week.
The AA eventually recovered my bike to my garage where I was able to check the battery voltage which was 12.57v.
My local Truimph dealer (5 miles away) is quoting 4 weeks before they can even look at it and are unable to collect it as they no longer offer that service.
The Datatool alarm was subject to a recall in 2017 and was replaced under warranty. It has work faultlessly since.
Any advice or guidance members can offer would be much appreciated..

 

UPDATE.

Had the bike thoroughly checked over by a qualified motorcycle electrician who traced the fault to the factory fitted DATATOOL alarm / immobiliser.

Choices were, remove & replace or simply remove.... Had it removed..

Considering the component is not subject to wear & tear, I would expect it to last more than 5 years therefore must conclude that it was not of satisfactory quality when fitted.

I would be interested to know how many other members have suffered similar problems & have had to pay out good money to have their factory fitted DATATOOL alarm / immobiliser remove.