[Users] POP3 to IMAP4?

[Michael]

I asked something similar some time ago but probably didn't express myself clear enough, so it gots not answered.

 * What happens if i copy all mails of a POP account over to a new IMAP account (which would be the same mail account on the providers side) ? I assume they get all uploaded ? 

 * What happens then if i copy whole folders with subfolders ? Will the folder structure be preserved ?

 * What happens to mail threads of other accounts, which are sorted into such subfolders, if i copy them over to IMAP ?

 * How can i adjust my 100+ filters with least effort, to work for the new IMAP instead the old POP maildir ?

I've got several hundred folders here (with many thousand mails, from several different accounts) and i would be happy to not need doing experiments.