I just checked USCIS website and my case disappeared with this message.
You must correct the following error(s) before proceeding:
Case Status Retrieval Failed
Status for this Receipt Number cannot be found at this time in this automated system. Please check your case receipt number to see if it is correct. If you have questions or concerns about your case status, please contact Customer Service at 1-800-375-5283.
Can someone confirm if this is the correct message when case disappears and file on its way to the DO?