Samsung’s latest foldables, the Galaxy Z Fold3 and Galaxy Z Flip3, are currently each receiving a software update in the US which brings with it the long-awaited support for eSIM, along with Dual SIM, Dual Standby (DSDS).
The new firmware builds are labeled F926USQU1DVEE for the T-Mobile Galaxy Z Fold3 and F711USQU2DVEE for the T-Mobile Galaxy Z Flip3, while for the unlocked models they are F926U1UEU1DVEE and F711U1UEU2DVEE, respectively. Hopefully the rollout will extend to other carrier versions soon.
As usual the updates might be going out in stages, so it could take a few days (or more) before every unit in the wild receives the update notification.
With eSIM support comes dual-SIM functionality – you can have one physical SIM and one eSIM working at the same time, through DSDS. The new updates also bring with them a lot of camera features first seen in the Galaxy S22 series. You get the June 2022 security patches too.
Source
