Purge locally document and avoid pull replication

Hi,
suppose i have an android application with Couchbase LITE 2.0 installed, with pull and push replication active in sync gateway. I have also a couchbase server 5.0.

Every document is associated with a channel, for example channel_company_"id_company".

Now, i’d like to create a document in the android app and push it to the server, and, when the end_datetime field is set( by the application), i’d like to purge my document from android app seen that i will no longer use it, but i need anyway to store the document in my couchbase server.

If i purge the document locally, the push replication will delete the remote’s one as well. I’ve seen that i could set document’s id to not push over, but would be very messy to track every document id.

How could i handle this scenario?