Updates being rolled out and then pulled due to issues has sort of become a new normal. From Xiaomi (earlier this year) to Samsung (quite recently), many big players pushed out major updates only to halt them “temporarily” to fix bugs.
Talking of US carriers, T-Mobile had to pull the Oreo update for the V30 and Note8, although the latter was resumed recently. However, what’s now coming to light is the magenta carrier is yet to resume a Galaxy S9/S9+ security update (G960USQU2ARC6/G965USQU2ARC6) it pulled last month.
Although T-Mobile didn’t officially reveal details on why the update was pulled, going by user reports, the update caused bootloops. Given that it was a monthly security update, there’s no point in expecting it to roll out now. However, we do hope a fresh security update will be pushed out soon.