SQL Server 2008 R2 - Change distributor schedule

We have configured SQL 2008 R2 replication. Distributor is configured in continuous mode, publisher is scheduler is set to execute after every six hours. Now we want to change distributor schedule from continuous to schedule frequency without re-creating new replication. We have tried below store procedure, but it gives error message. Please help to distributor settings.

EXEC sp_changepublication @publication = 'your_publication_name', @property = 'allow_anonymous', @value = 'false' GO

EXEC sp_changepublication @publication = 'your_publication_name', @property = 'immediate_sync', @value = 'false'