Many thanks to those who took the time to reply to my recent enquiry regarding the mysteries of the expiring NIE certificate.Very helpful
Those equally helpful (?) folk at the London consulate confirmed that a NIE certificate is valid for 3 months (as stated on the certificate) and that it is necessary to re apply to replace an out of date one for any transaction requiring a certificate.
The word on the web indicates that in practice this rather depends on who one is dealing with.( Surprise,surprise !).
And lo! This came to pass. Regarding the making of a Spanish will, I have been told today that one notary approached required an in-date certificate and another one didn’t. (More surprises, but no prizes for guessing who got the job as it saves me a costly and time consuming trip to the metropolis ).