It seems that MigrationWiz had a performance bottleneck related to Inputs/Outputs (IOPS) and this meant we could only extract 2 users' mailboxes at a time.
This was my experience a year ago, and I was wondering if this issue is likely to occur again, or whether the code has been improved to overcome this issue?
We don't know how much data the client has, or how big the mailboxes are. Apparently larger mailboxes take a long time due to the IOPS issue, and our concern is that if there are a lot of large mailboxes we might struggle to achieve completion in the required timeframe, which is 6 months, starting in late February.
We are trying to understand if the issue referenced by your team last year has been resolved. If not, we will seek to get some analysis on the archive mailboxes, estimate the size of the dataset, and use our past experience to determine if we can complete in time, before committing to the client that it is achievable.
If it has been resolved, that will give us a higher level of confidence, and we will be able to move forward with scoping the project, and committing to the required timeframe. Look forward to hearing from you.