It seems you're encountering difficulties migrating your historical payroll data from QuickBooks Desktop to QuickBooks Online. I understand your concern about accessing your historical payroll data after the 2023 tax filing season. 

To shed some light on this matter, let me inform you that QuickBooks Online does not automatically migrate historical payroll data from QuickBooks Desktop. However, if you want to access your historical payroll data after the 2023 tax filing season, maintaining an active subscription to QuickBooks Desktop may be necessary. Alternatively, you can explore options for accessing the historical QuickBooks file on your server without incurring additional costs.

You can use the standalone QuickBooks Desktop software to access the historical payroll data without an active payroll subscription. This software allows you to view and research historical payroll information without the need for an ongoing subscription.

Know that when moving from QuickBooks Desktop to QuickBooks Online, you may notice differences in how your books appear due to the import limitations. Particular data do not move in QuickBooks Online, including wages. To learn more about the features and data that move from QuickBooks Online to QuickBooks Desktop, refer to this article: Learn how features and data move from QuickBooks Online to QuickBooks Desktop.

I'm also adding this article to learn how to import only your payroll info from QuickBooks Desktop Payroll to QuickBooks Online Payroll: Move your QuickBooks Desktop Payroll info to QuickBooks Online Payroll (payroll only).

If you have more questions about moving your QuickBooks Desktop data to QuickBooks Online, post them here in the forum. I'll be sure to answer them ASAP! Have a great day ahead!