SIM card usage - How to switch SIM cards at the specific time of day?

Assuming that we want to use SIM1 from 00.00 to 06.00, SIM2 from 06.00 to 12.00, SIM3 from 12.00 to 18.00, SIM4 from 18.00 to 06.00- so we cover all 24 hours.

In order to process this you should go to the menu Gateway control > GSM outgoing groups and choose the proper group. Set Mode of switching SIM card to By Time. In field Time to switch to another SIM card set Time for SIM1 from 00:00 to 06:00, SIM2 from 06:00 to 12:00, SIM3 from 12:00 to 18:00, SIM4 from 18:00 to 06:00.