This was done by taking the gitlab redirections and turning it into a
sed script, mostly by hand.

service/email.md

@@ -1245,8 +1245,8 @@ time:
 
 ## Submission server proposal
 
-Note: this proposal was discussed inline in the old
-[howto/submission](howto/submission) page, before the TPA-RFC process existed. It is
+Note: this proposal was discussed inline in the 
+[email](service/email) page, before the TPA-RFC process existed. It is
 kept here for historical reference.
 
 The idea is to create a new server to deal with delivery problems