Hi,
I have just checked up the info you have and the record states that TYP722 is actually licensed at present, interestingly it also reckons the bike is now black! so it has had a change of colour in the past 50 years!
The info on vehicles that are recorded with the DVLA seem to fall into three categories:
A future date of Liability is quoted and the comment given "License not Due", which according to my taxed Dragonfly record shows it as actively licensed, the date given is the renewal date as quoted on my V5C.
A future date of Liability is quoted and the comment given "Sorn not Due" which is the designation given to my sorned Honda. Which of course like the tax needs renewing annually.
A future Date of Liability is quoted and the comment given "Not Licensed" this implies that the vehicle was registered as "off the road" with the DVLA before the introduction of SORN but it is still on record. It seems that the DVLA update this information themselves. This is confirmed by my Mark 5 which has been "not Licensed" since the introduction of the V5 back in the eighties.
Must rebuild it soon before I am too old to ride it 
So it would seem that TYP722 is alive and well albeit now in black livery, just like my own Dragonfly!!
I hope this information is of use. I suggest the next step is an advertisement in the London Douglas MCC magazine as we have many members that do not use the web.
Dave