When will T-Mobile version of OnePlus 10 pro receive the OxygenOS 13 update?

Hey all. You can keep an eye on where we are in the development cycle for the latest update by visiting our Support site. Here is the direct link to the Android updates page: Actualizaciones de software Android | Asistencia de T-Mobile

We don't have dates listed because things can happen that can cause delays. The main update is completely developed by the manufacturer, but we have our own requirements and features that need to be added too. Sometimes we do those additions ourselves and sometimes it is part of the build that the manufacturer does. Either way, we don't want something released that will brick your phone or cause serious headache, so lots of testing has to be done. The OnePlus 10 line is still in development, so additions and tweaks are still being made. 

Sounds like you are all doing the right thing by checking for updates regularly, so you will see it as soon as it is polished and ready.