I'm here to point you in the right direction to take care of this, @Buck Tsai.

I tried to check on our end but didn't find any offer about a migration service for Sage Pastel Partner.

If you wish to convert data from Sage Pastel Partner to QuickBooks Online, you can follow the steps provided above. 

Otherwise, contact our support team directly or the Pastel Express Suppor Team. They'll be able to guide you through the process to ensure the data is transferred accurately.

I've also included some common questions about importing data. This will serve as a guide through the process: Frequently Asked Questions about Transferring Data to QuickBooks Online.

Feel at ease to comment down below if you have any other concerns about migrating data from Sage Pastel Partner to QuickBooks. I'm always glad to help in any way I can.