Both devices, although only the ones available via T-Mobile carrier are getting their updates as we speak. Rollout began on April 13, so it may very well be over by now. Galaxy S9 now sports a build number G960USQU2ARC6, while Galaxy S9+’s is G965USQS2ARD3. According to T-Mobile’s fast and specific patchnotes, they contain, quote, ”various bug fixes”.