Hello, I am using advanced rewriting with user id and virtual /member/ folder. When someone changes his username, seo still redirects users when presing on new username to old user profile(whick actually doesn't exist). Evrything works perfect after I purge the cache, but I cant purge cache after each username change. How to fix that?

Profile url without id (example.com/user/nickname/) won't work any more after user name update, only the ones with id (whatever the other options) will be http 301 redirected to the new ones.
I don't see how cache could be related to this, unless we're in fact talking about browser cache (which could be updated after phpBB one is since it could alter the last modified headers).

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