This only applies if you purchased your extension via Magento Marketplace.
Sometimes you install an extension you purchased from Magento Marketplace and immediately notice that a newer extension version is already available. For example, by going to System > XTENTO > Configuration, which display your installed version and the latest version available.
Magento Marketplace reviews each and every update we submit to them carefully. Thus, it can take up to 4-6 weeks until an update we submit to Magento Marketplace is released and can be installed by you. This causes the delay - you can see a newer version is available, but not on Marketplace as the Marketplace QA team is still reviewing the update.
In this situation, if you notice a bug in the extension or need the latest extension version for whatever reason, please reach out to firstname.lastname@example.org and mention your MAGID (Magento Marketplace ID) and/or Marketplace order number and that you're looking for the latest extension version. We will be able to send you the latest version then, provided you're still within your support and update period.