XF 1.5 Update all users that are watching threads with email


Active member
I have a large number of users that signed up early on with "watch all threads created and replied to" selected WITH E-MAIL.

This was of course annoying and I then changed it to with alerts only.

I want to change all users that are watching with email to watch with alerts only.

Almost none of my users want email, but many don't know how to turn it off.

Thank you for any assistance.