HTTP status codes / 3xx — Redirection
308 Permanent Redirect
What it means
Permanent like 301, method-preserving like 307. A POST redirected with 308 is re-POSTed to the new URL.
What causes it
API endpoint migrations where method and body must survive the move.
How to fix it
Nothing on the client side. API authors: 308 over 301 when redirecting non-GET traffic.