Are you thinking that an FCL 945 authorisation is good for national licences as well as EASA ones?
That question is a good one, but finding the answer doesn't seem to be obvious.
I've spent hours of my day searching various publications after I was asked by an NPPL holder to sign his licence for re-validation by experience.
When I started instructing >30yrs ago the licencing rules were so simple .... its now an appalling mish mash of licence types,
Hopefully when we leave EASA things might improve for the better with a simplified system.