Docs: vttablet PITR via --restore-to-timestamp and --restore-to-position

content/en/docs/18.0/reference/features/recovery.md

@@ -6,7 +6,7 @@ aliases: ['/docs/recovery/pitr','/docs/reference/pitr/']
 
 ## Point in Time Recovery
 
-Vitess supports incremental backup and recoveries, AKA point in time recoveries. `v17` offers restore-to-position functionality, and `v18` is slated to support restore-to-timestamp functionality in addition.
+Vitess supports incremental backup and recoveries, AKA point in time recoveries. It supports both restore-to-timestamp and (one second resolution) as well as restore-to-position (precise GTID set).
 
 Point in time recoveries are based on full and incremental backups. It is possible to recover a database to a position that is _covered_ by some backup.
 

content/en/docs/18.0/user-guides/operating-vitess/backup-and-restore/bootstrap-and-restore.md

@@ -9,8 +9,10 @@ Restores can be done automatically by way of seeding/bootstrapping new tablets,
 
 When a tablet starts, Vitess checks the value of the `--restore_from_backup` command-line flag to determine whether to restore a backup to that tablet. Restores will always be done with whichever engine was used to create the backup.
 
-* If the flag is present, Vitess tries to restore the most recent backup from the [BackupStorage](../overview/#backup-storage-services) system when starting the tablet or if the `--restore_from_backup_ts` flag (Vitess 12.0+) is also set then using the latest backup taken at or before this timestamp instead. Example: '2021-04-29.133050'
-* If the flag is absent, Vitess does not try to restore a backup to the tablet. This is the equivalent of starting a new tablet in a new shard.
+If the flag is absent, Vitess does not try to restore a backup to the tablet. This is the equivalent of starting a new tablet in a new shard. If the flag is present, then the tablet is seeded by a backup, as follows:
+
+- If `--restore_to_timestamp` or `--restore_to_position` flags are provided, then this is a [point in time recovery](../overview/#restore-types). The tablet auto selects a good full backup followed by a series of incremental backups, that collectively bring it up to date with requested timestamp or position. The tablet is set to `DRAINED` type, and does not begin replicating.
+- If neither of these flags is present, then the tablet is running a _full_ restore. Vitess tries to restore the most recent backup from the [BackupStorage](../overview/#backup-storage-services) system when starting the tablet. Or, if the `--restore_from_backup_ts` flag is also set then using the latest backup taken at or before this timestamp instead. Example: `"2021-04-29.133050"`
 
 This flag is generally enabled all of the time for all of the tablets in a shard. By default, if Vitess cannot find a backup in the Backup Storage system, the tablet will start up empty. This behavior allows you to bootstrap a new shard before any backups exist.