For the production models amongst dual SIM slots, the alternative "Preferred network type" inwards “Settings” -> “More…” ->”Mobile networks” is alone for the SIM menu which is appointed to piece of occupation for information service network afterwards upgrading to V2.21.40.44
(After upgrade to V2.21.40.44)
(Before upgrade to V2.21.40.44: both SIM cards available for setting)
