How to configure UL frequency for NB-IOT ?

In NB-IOT, UL freq is configurable by the network via SIB2. However, UE SIM can not change dynamically the UL Freq based on SIB2 parameters.  For that, UE SIM UL freq should be configured manually in the UE config file.  Thus, SIB2 should be known in advance in order to set UL freq in UE SIM config file. Both ul_earfcn and ul_carrier_freq_offset can be read from SIB2, then we can easily configure on UE SIM config file ul_earfcn and ul_carrier_freq_offset.