Yes you can upgrade to the latest version. If you are not located in the US, you can purchase from a reseller/partner without the credit card if required. If you don't need any specific requirement to use QB Desktop Enterprise, you can cross-grade to the lower edition. You can still purchase the one time license for QB Desktop 2021 Premier or QB Desktop 2022 Premier Accountant.

Where is your company located? If you are not located in the US, you may consider to purchase a 3rd party service to convert data to QB Online.

What do you mean with "update"?

Do you need to update your release version for your existing QB Desktop 2015 (i.e R17 is the last version) or upgrade to QB Desktop 2022 Enterprise? 

Hi there, Custom Tag.

Let me help upgrade your QuickBooks Enterprise 2015 to the latest version. There are five ways to do this process depending on your business needs.

• Upgrade your QuickBooks Desktop subscription
• Upgrade QuickBooks Desktop without a subscription
• Use the Discovery Hub to upgrade
• Upgrade tool can't find my QuickBooks Desktop purchase
• Upgrade QuickBooks within the Right Networks hosting environment.

For complete instructions and detailed steps, please browse this article: Learn how to upgrade to a newer version of QuickBooks Desktop from within the program. It'll tell you how to install and activate the program.

Please know that the latest release of QuickBooks Desktop Enterprise 2022 is R5. You can find more details about it through this page: Release notes for QuickBooks Desktop 2022. After you upgrade QuickBooks, you also need to upgrade the company file. 

On the other hand, about moving to the cloud, I recommend contacting your hosting service provider. They can help migrate your company profiles using the newly upgraded version.

You can come back to this thread whenever you have additional questions. The Community forum is always open to help you.