Unable to allocate replica shard after node restart

Thank you @Bernt_Rostad & @Steve_Mushero

Since Elasticsearch deletes old local primary shard after it adds the replica, there is a moment when it needs almost double storage. So, is there any way to delete these old shards beforehand ?

Also you mentioned

We just need it to do this fast enough to not hit the watermark again.

How to make it fast ?