Phases for data synchronization stage

While in the synchronizing phase, you should not attempt to initiate object changes on the copy node. Migrate While Active is actively synchronizing changes from the source to the copy node, and the copy node is not ready at this point to be used. Db2® Mirror replication-eligible objects will prevent any attempt to initiate an object change on the copy node. Non-Db2 Mirror replication-eligible object types and objects within the integrated file system have no blocking protection in place on the copy node.

It is only after data synchronization is finalized and a role swap has occurred that changes to objects are permitted on the migrated copy node.