From what I’ve read if you use the remote release for the charge plug it has to be reset by the garage afterwards.
As for the difference in economy mode I’ve never really used it except to try it for a few minutes, given the savings on petrol I really don’t bother driving for the best economy any more. I just drive A to B and it is what it is.
Please excuse spelling/typos. Apart from being a clot it turns out I had one on my cerebellum that's now causing various problems!