Large number of commands in the distribution database waiting to be applied to subscriber
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I am using transitional publication with updatable subscribers SQL replication. I updated the database schema with new tables, views, and indexes. Since the update, 2 days ago, there is still a high number of commands waiting to be applied to the subscriber. I have tested ddl and dml commands and both instantly replicate without a problem, even though the replication monitor shows this backlogged queue. 

Anyone know what these commands that are waiting to replicated? And why does replication currently work, with this backlog. I was under the impression that replication was first in first out.

Using Microsoft SQL 2008 R2.