Changing route and still ending on the same shard (or increasing the % of shards a tenant is distrbuted on without reindexing)

[Dorian Hoxha]

Hi,

Assuming I use `tenant1/4!doc50` for id (which means 1/16th of shards), and
I later change it to `tenant1/2!doc50` (which means 1/8), is it guaranteed
that the document will go to the same shard ? (it would be nice, but I
don't think so). Meaning , when you change the `/x!`, do you have to
reindex all data for that tenant ? (if not, is there a way without fully
reindexing a tenant?) This probably will also fail because the id changes,
but what if using another field for _routeing and id stays the same ?

Thank You