My old blog is no more. Existing links will (slowly) give a 404. I'm working on getting a new domain structure which I control, so that in the future I can put my own redirects in place etc, but I can't do that retroactively with the old posts.
When my new blog is up and running and I'm confident in the new structure, it would be really helpful if I could provide Stack Exchange with a map of old URL to new URL, and the fix-up be done automatically for all posts and comments, regardless of who made them. I could write a tool using the Stack Exchange API to do this for posts, but it feels like the kind of thing that would be best done by the Stack Exchange team, potentially without changing the last-modified date and edit record (as it's not a useful semantic edit, just a change of navigation). Additionally, that would allow for changes in comments and deleted posts which I couldn't otherwise edit.
Is there any facility for this already?