Hello there, @Questionable.
I'll help share further details about uploading transactions after converting from QuickBooks Desktop (QBDT) to QuickBooks Online (QBO), so you can manage your data accordingly.
You can convert your QBDT file into QBO within 60 days after you sign up to avoid messing up your data. With this, I agree with the options that @Fiat Lux - ASIA provided.
When you've already entered seven months of new data in QBO, you'll have to manually upload your transactions (via Excel spreadsheet) that you entered in QBDT after the conversion process. To do this, you'll need to export your list from QBDT and import it to QBO.
In case you're uploading bank transactions, please refer to this article for the complete guide: Manually upload transactions into QuickBooks Online.
Also, you may want to check out these articles as your reference on how your books will move from QBDT to QBO and learn more about the steps you should take after moving your file to make sure your data is ready to go:
Keep me posted on how it goes in the comments below. If you have other importing concerns or questions about managing your QBO data, I'm always ready to help. Take care, and I wish you continued success, @Questionable.
