Actually there are two different Programs for OneDrive, the OneDrive Sync Client (which is preinstalled in Windows 10 and automatically updated in the background without any user notice), and the Microsoft Store App OneDrive (which is also available for Windows 10 Mobile, Xbox One, Holo Lens and Hub, and also automatically updates via Windows 10 Store, if specified so in your Store settings).
You are probably referring to the Sync Client, which automatically syncs your OneDrive folder with your OneDrive cloud storage, and any other devices you use with the same Microsoft account. The Sync Client receives all updates automatically, but not via Windows Update. Additionally, the updates are not always provided to all your Windows 10 devices at the same date (but they will receive the updates regularly).
I think there is still confusion about OneDrive’s Store App and the Sync Client (as is with Microsoft Outlook, which is mentioned when speaking about the Windows 10 App, but also when speaking about Office Outlook and also about the web feature; but all are completely separate programs or features…)