Software updates

I am wondering if a software update would stop the enige from being started!

I have a Jaguar XJ (2019) and  had a 46 mile drive from home to a place of work driving maily on a motorway. There was no problem during the journey and the car needed a good run out. 

The vehicle had been parked up for around 5 and a half hours and when I returned to it the engine would not start when I pressed the Start/Stop button. The engine did not turn over only the lights came on but not a sound from the engine. I called Jaguar Assist and they were very helpful and within 10 minutes assistance arrived. 

After an hour checking everything it was decided that the car was going nowhere and would have to be recovered. As it was past midnight Jaguar provided transport for me to get home and the car was delivered the following day to a Jaguar dealer. When I collected the car 3 days later I was told it needed a software update and that was the reason why it would not start.

I find it rather hard to believe that this is the case and I have a bit of doubt and think that the Ad-blu had not been topped up during the last service. 

Has anyone had a similar experience or is this correct that a software update would stop the car from operating normally?