Let me share what I know when importing data to the Desktop version, Cinderella.
The invoice number will not sync. You'll want to change the number manually when it's imported to QuickBooks Desktop.
However, it will not change the sequence. The sequence will only be changed if the invoice is created in the Desktop version, not in POS.
I'll include this reference to help you learn more about the process of sharing information between these two programs: Financial Exchange Overview.
Get back to this thread if you have additional questions about the importing process. We'll reply as soon as we can. Take care!