Could I remind everybody that somebody died here. The reasons for this have yet to be determined, but they ultimately will not be about the paperwork, they'll be about the aeroplane and the pilot. So, whilst of interest, the status of the registration, PtF and the PiC's licence(s) are not what actually caused the accident. That was something physical - perhaps weather, perhaps how it was flown, perhaps a physical failure. But it wasn't the paperwork.
Having said that, yes I believe it's entirely possible either that it had been re-registered but G-INFO hadn't been updated: the lag is generally a few weeks, or that the owner intended to use the permit renewal to get the aeroplane re-registered. If this was a check flight, then the check pilot was insured by the BMAA; if it was a private flight shortly afterwards then potentially the insurance had just been renewed on the phone. All quite legal.
Or it was an illegal flight, of a de-registered aeroplane with no current Permit to Fly. That also fits what we know at the moment.
But again, the paperwork did not cause the accident.
Flexwings, like any other aeroplane, bite if stuff goes wrong. That tragically happened here. So far as I know, nobody knows enough right now to piece the reasons together, but I'm sure this will come together shortly. The photograph indicates a near vertical collision with an intact aeroplane. That could be a low level stall, a tumble, or a cable failure. Or something else.
The type, a Gemini F2a had an inglorious early history and quite a few fatal accidents due to loss of control. However it has been perfectly safe over the last decade and more since various modifications were mandated. It is however known to have a wing that is intolerant of not being correctly set and maintained. I've no doubt that somebody's already told AAIB about that.
G