OpenSearch upgrade leftover persistent settings

Hello,

After OpenSearch upgrade we note that these entries have been added to the persistent settings of the clusters:

{
  "persistent" : {
    "plugins" : {
      "index_state_management" : {
        "metadata_migration" : {
          "status" : "1"
        },
        "template_migration" : {
          "control" : "-1"
        }
      }
    }
...
}

I haven’t found any documentation around them but I guess they were used to coordinate the migration. May I delete them now that clusters are happily upgraded? Is there any documentation around these that I missed? Many thanks in advance.