Once I switch to qbo I am unable to access qb desktop, correct?

Welcome to the Community, @langstonconst-ci.

You can still access your company file in QuickBooks Desktop as long as you have the backup copy.

Let me guide you on how to restore a backup copy.

1. Open QuickBooks, go to the File menu 
2. Choose Open or Restore Company.
3. Click Restore a backup copy and then Next.
4. Select Local Backup and then Next.
5. Find your company file. It should look like this: [Your company name].qbb.
6. Once you found it, click Open.

In case you need to import your QuickBooks Desktop company file to QuickBooks Online, here's an awesome article that you can look into: Move your QuickBooks Desktop file to QuickBooks Online.

If you need further assistance, don't hesitate to click the Reply button. I'd be glad to help you as soon as I can. Have a great day!

@langstonconst-ci 

You may keep working on your QB Desktop file if required or manage dual bookkeeping.

Once you are ready migrating to QB Online, make sure to click the Buy button to get the discounted price for up to 6 months. If you purchase from the trial account, you have to pay the regular price.

https://quickbooks.grsm.io/US

https://quickbooks.grsm.io/us-promo