The remaining steps for session storage rollout are:
- [x] Update `testwiki` from `kask-transition` (multi-write w/ redis) to `kask-session` (Kask-only)
- [ ] Update the remainder of testwikis to `kask-transition` (multi-write w/ redis)
- [ ] Update the remainder of testwikis to `kask-session` (Kask-only)
- [ ] Update phase0 to `kask-transition`
- [ ] Update phase0 to `kask-session`
- [ ] Update phase1 to `kask-transition`
- [ ] Update phase1 to `kask-session`
- [ ] Update all remaining wikis (`default`) to `kask-transition`
- [ ] Update all remaining wikis (`default`) to `kask-session`
(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).