If I import a list of emails it does not check if the imported emails already exist in a customer account and it creates a new "newsletter only" record of the dupe email - this causing trouble when the customer tries to update their profile etc.

Is there any fix guides for this?

Would I be better off just exporting all my current emails as a list and comparing the two lists before import?

BTW: there is a typo at the top of the readme.txt file, hence my typo heading because I copied and pasted - DOH! ;)