https://www.theverge.com/2018/3/19/17139748/android-oreo-update-samsung-galaxy-s8-plus-us-tmobile-sprint-verizon-att

Samsung has confirmed that it has completed its Android Oreo beta tests and has officially begun sending out the software updates to Galaxy S8 and S8+ devices in the US. “After completing extensive testing and beta tests that are standard when we launch a new Android update or product, we are beginning to roll out Android Oreo to select US Galaxy smartphones, starting with the Galaxy S8 and Galaxy S8+,” a Samsung spokesperson told The Verge. “Galaxy Note8 will follow shortly thereafter.”

When exactly you’ll see this update depends on your carrier; so far, users have reported receiving their Oreo updates on T-Mobile, Verizon, and Sprint. Samsung briefly halted Oreo rollouts last month after the update cause some phones to randomly reboot.