https://www.techradar.com/news/windows-10-may-2019-update-is-now-available-but-only-for-some-pcs

We guessed that the May 2019 Update would be arriving this week, and Microsoft has indeed just kicked off the rollout of the next big upgrade for Windows 10.

While the May 2019 Update is now officially available, Microsoft is taking what it describes as a throttled approach to the rollout. Basically, you can check on your PC for the update, but it might not be available to all that many users initially.