Thanks again for your advice. I’ve checked all my domain settings and there’s nowhere to redirect to https there. I’ve also got my hosting company to re-check all their settings and they couldn’t find anything for a redirect to https – they thought the only thing was the https in the wordpress settings.
So I added the redirect to https code into my htaccess and BINGO! the super long redirect from the http url has reduced to a minimum. Should have done it right at the start after I was sure the certificate was all sorted and everything was via SSL – I was just a bit nervous of this when told it could create endless redirect errors.
So I shall continue to pursue the caching plugins and ask my host to look at their Time to First Byte too – which should speed it all up.
Many thanks again. Cheers.