Thanks for the replies guys, much appreciated, especially the offer of tools
I don't have roadside assist but I may get some happening to get through this issue.
I woke up early and checked on the car - connections, cables, wires.... used my scanner to see if there were any issues and none were found. The only errors that were reported are related to low battery voltage (which makes sense) and the battery charge level was constant at 12.5V. So, I am sure that the problem is not the battery but something else.
After checking the car out, I went for a drive to check for issues whilst running and driving and the car was flawless.
Has me baffled at the moment and if it is an intermittent problem, it could be harder to diagnose.
All of the BMW service places I have rung this morning are closed except for BMW Southport and I am leaving it as the last option to visit a dealer. I tried Euro Tune and Euro Tec and some others.
Now looking for an auto electrician that is actually open.... any other ideas, keep them coming. I'll post with updates in due course.