I have just looked up the details for a new multiple entry non O visa from the Liverpool Thai consulate. It appears that it is necessary to spend 48 hours outside Thailand before making a new entry. Is this a new and enforced rule ?

Nope.

Leave Thailand, enter another Country, turn round and go back again if you wish.

From Liverpool website. The 48 hour bit is not the only piece of wrong information given.

People visiting family – i.e. men who are married to a Thai National, along with your visa application you must produce your marriage certificate and a translation of the certificate is required as evidence. A single entry visa is valid for 90 days and can be extended for a further 30 days. A multiple entry visa is valid for 12 months conditional on leaving Thailand for 48 hours every 90 days.

Thanks for that . I got a non O multiple entry visa in Gibraltar last year , the hon consul did want a copy of the marriage certificate and translation , to send to the Thai London Embassy. think will use him again .