In Staged rollout when updated application will be displayed on play store

Playstore decides the 1% of the users who will be seeing the update. You might or might not be one when u visit your app page.

You can see the no.of downloads on App Releases - > RollOut section

As your staged rollout percentage is only 1% it might not cover you or the accounts you're using.

==> App update will be available to the percentage of users in your staged rollout, but it may take time for the full group to receive the update. You might be the user who isn't covered (by the rollout), so update notification will not fired to you.

It may be noticeable that: If you choose specific countries for your staged rollout, the upgrade will be limited to users with Google Play accounts in those locations.

And yes there may be no criteria for choosing user base for staged rollout percentage.

Comment below if you have any doubt.

Happy Coding...