Apparently it lasted about 14 hours. This morning after the software update by the dealer, BSOD again, so call out Jaguar assistance again.
Update: Jaguar Assist Engineer re-installed S19A. He had wanted to revert but was unable to do so. He spent an hour and a half and I have the same S19A that had just failed. We will have to see. During conversation he suggested that OTA might fail if, during the process, the battery voltage drops slightly for any reason. I am now trying with Software updates locked and Updates switched off to see if I can manage to get a working vehicle for more than a couple of days. If voltage is critical, then maybe updates should only be allowed with the vehicle 'on charge' and with the drive battery charging the 12 volt battery. Who knows? .
The statement that "updates keep the vehicle performing at its best" may not be true.
Also discovered that this reset had removed all settings, vehicle was displaying all default values and the Route Planning App had lost connection and was reporting the vehicle at the dealership; the InControl App meanwhile was reporting correctly.
Update 2 - 16 Mar 2019
I have been ICE'd. This morning going out to Worthing and again BSOD on the Centre and lower screens. Contacted Jaguar Assist. They agreed to send out an engineer (same one as yesterday they stated). Then I received a call from Jaguar Mobility who told me that when the Engineer had re-enabled the software, I should take the vehicle to my dealer and they would provide a replacement. After an hour of waiting I contacted Jaguar Assist who told me an engineer was en route. After another hour and a half, I was then getting concerned that my dealer service department was going to close soon. I called the dealership who reportedly knew nothing about it but if Jaguar Mobility did deliver a vehicle then sales would hold on to the keys if their service department was closed. Called Jaguar Assistance to find that the call had been closed and the engineer cancelled. No one had informed me. "Could I take the car to the dealer?". This I then did (still with no centre or lower displays). On arrival, dealer still knew nothing. Waited for 20 minutes and then I was given an XF estate, very nice but not nearly in an I-Pace class. So off to Worthing (very late) and having to look at fuel prices again. Heigh Ho. It will be very nice when my car has working software. The Outlander PHEV was a little agricultural but at least the software worked.