Thank you all for the advice, much appreciated.
I went direct 1.2.1 to 1.4.14 and can confirm that it does work.
All done. Phew, was a mission on a big site as I had to make lots of tweaks. Actioned in a test site first to make sure it worked. Sticking to legacy Ditto and Wayfinder etc in this particular site for now - lots and lots of filters and calls throughout the 3,500+ page site - the latest versions are working fine. At some stage I will changeover to DocLister, DLMenu, FormLister etc on this site, but not for now.
Many thanks again and have a super day.
risingisland Have you ever had any admin login problems after an update?
Yes. All the time. The "GoingOn2" addition to the manager url link at the end of the update never seems to work for me. After updating I manually remove "GoingOn2 etc" to make the normal manager url, then I can login fine.