until v6.x is fully ready, the v5 website will stay available read-only (maybe only the guidebook), for instance "incident reports"
[ ] use a special subdomain for v5 pages
[ ] switch v5 to read only
[ ] make a 301 (permanent) redirection for migrated documents (waypoints, routes, outings etc.). Such v5 pages should no longer be accessible => always redirect to v6.
[ ] make a 302 (temporary) redirection (?) to v5-subdomain URLs for not migrated document types
Redirections from old v5 URLs to new v6 URLs are needed: