Starting 3:30pm, Amazon has documented Feeds and Reports errors are higher than normal.
Roughly starting 5:00pm and waning by 6:00pm SKULabs has documented an uptick in inventory feed processing times from Amazon. This can result in overselling if your multi-channel inventory sync does not have any safety stock.
Now would be a great time to make sure you're following our best practices for Black Friday/Cyber Monday.https://help.skulabs.com/en/articles/3925024-setting-up-a-safety-stock-strategy
Reminder: Amazon will not accept a ticket for any inventory feed that takes less than 24 hours to process. This means you need at least 24 hours of safety stock or you need to completely segment your inventory across each channel so no overselling is possible. See our guide above for more details.
Check MWS Status for updates: http://status.mws.amazon.com/