ResolutionMigration timeout is set to 3600 seconds (1 hour) by default in VZAgent configuration. You may modify it via VZMC as following:
1. Right-click on source hardware node in VZMC
2. In the appeared context menu choose 'Tasks > Manage VZAgent Configuration'
3. In the dialog appeared go to 'hwm > configuration > timeouts' section
4. Increase the value of 'migrate' parameter and click "Apply"