title: Couch DB replication - Sequence number in 'since' param is invalid
body: <p>We have an android application which uses CouchBase Mobile. This application replicates from CouchDb on Cloudant. </p>
  
  <p>We recently observed that (when replication started taking more than 6 minutes to 'complete') that the 'since' parameter sent in the 'changes' request is no where near the source's sequence number. </p>
  
  <p>Source's SEQ = 66000+</p>
  
  <p>Since param on 2nd and subsequent replication requests  = 25000+ (it varies) </p>
  
  <p>We use a filter, which actually takes a lot of time,  and we are OK with it for the first replication. But we see that future replications takes 6 minutes (even when there are no updates at source  db).</p>
  
  <p>We suspect that for the filtered replication the target only makes a checkpoint for the last replicated doc and <em>not</em> the source's commit sequence. </p>
  
  <p>Is this the default behaviour? Is there a way to overcome this feature/problem?</p>
  
  <p>[We are in the process of migrating to CouchDB Lite, but we need to fix this before that].</p>
  
  <p>Regards,</p>
  
  <p>Vijay </p>