Google Pixel 3a and Pixel 3a XL pre-installed the old March 5 Android security patch, rather than the May 5 patch on the high-end Pixel model. If you look at the Android Beta program on Google’s website, you’ll see that the new machine doesn’t appear in the list of Pixel phones that are eligible for Android Q Beta preview.
The good news, however, is that Pixel 3a and Pixel 3a XL will soon be welcoming the Android Q Beta. The page on the Android Beta Program website shows that Pixel 3a and Pixel 3a XL will be eligible to install the Android Q beta from next month. The fourth beta of Android Q is expected in early June, so speculate that Pixel 3a/3a XL will receive the June Android security patch at the beginning of next month.
Although Pixel 3a and Pixel 3a XL are currently unable to officially install the Android Q Beta preview, it seems that some Pixel 3a users have been able to install the latest beta preview of the Android Beta preview site above. To see if you can, please Click here and click on “View your eligible devices.” If your Pixel 3a or Pixel 3a XL appears in the list, then you can install it. If not, then you have to wait three weeks.