Google Apps limits the amount of data that can be accessed, via IMAP, in a 24hr period (Updated in April 2017 to 10GB or 10240MB via IMAP in a 24hr period). On Demand Migration for Email (ODME) is designed to work around this limitation by allowing you to set a limit within ODME, that is lower than the expected end-user bandwidth usage.
For example, if you anticipate that the end-user will use more IMAP traffic in a 24hr period, then you can limit ODME to use an amount under 10GB. Once ODME has used it's 10GB quota for the 24hr period, then it will reschedule the migration to continue in 24 hours.
However, there have been instances where for particular users, Google Apps was disconnecting ODME from migrating data instantaneously. After waiting 24 hours and restarting the migration, the same issue would occur. In this case, there may be other third-party applications using up IMAP traffic that has not been accounted for.
The following steps will help troubleshoot this issue by temporarily suspending IMAP access to the end-users account. After the user's IMAP access has been suspended for 24 hours, then it should be re-enabled and the user should be migrated with ODME using a new Migration Plan.
The easiest way to disable IMAP access will be to Suspend the source Google account – Please note! Following these steps will completely disable access to the source mailbox until it is manually re-enabled by following the same steps. Only perform this action if the source mailbox is indeed not in use.
If the source mailbox still needs to be accessed via the Google Apps UI, we can instead just disable IMAP access with the following steps. This way the user will still be able to access their Google Apps data using the Google Apps web UI: