I have found the example using nRF52833 in the latest SDK (ble_app_att_mtu_through....)
I am using Keil uVision 5.29.0 and I have downloaded the software packs 8.27.1, 8.28.0 and 8.29.0
But I cannot find a functional configuration.
In most configurations I get errors related to the errata files.
With runtime configuration set for 8.28.0 and only Device Startup (no StartupConfig) I get an error that #include "nrf_erratas.h" does not exist!
With including also the runtime StartupConfig version 8.28.0 I have the same error erratas header cannot be found.
If I change to 8.29.0 the include file is found but has an error. (static bool errata_1(void) __UNUSED; expected {.....)
It is someway dissapointing that the only example available for this chip does one run in a supported development environments! :-(