The remaining steps for session storage rollout are:
- [x] Update `testwiki` from `kask-transition` (multi-write w/ redis) to `kask-session` (Kask-only)
- [x] Update the remainder of testwikis to `kask-transition` (multi-write w/ redis)
- [x] Update the remainder of testwikis to `kask-session` (Kask-only)
- [x] Update group0 !!& group1!! to `kask-transition` ([[ https://gerrit.wikimedia.org/r/#/c/operations/mediawiki-config/+/569678 | r569678 ]])
- [x] Update group0 !!& group1!! to `kask-session` ([[https://gerrit.wikimedia.org/r/c/operations/mediawiki-config/+/570393|r570393]])
- [x] Update group1 to `kask-transition` (skipping...)
- [x] Update group1 to `kask-session` (skipping...)
- [ ] Update all remaining wikis (`default`) to `kask-transition` ([[https://gerrit.wikimedia.org/r/c/operations/mediawiki-config/+/570395|r570395]])
- [ ] Update all remaining wikis (`default`) to `kask-session` ([[https://gerrit.wikimedia.org/r/c/operations/mediawiki-config/+/570396|r570396]])
(WARNING) Each step from `kask-transition` to `kask-session` should be spaced apart by either a) `$wgObjectCacheSessionExpiry` (1 hour), or b) the amount of time necessary to be confident everything is working as expected (which ever is longer).