Disclosed is a method for scheduling transmissions of multiple carriers from a single transmitting network node (10; 100) for multiple Narrow Band Internet of Things (NB-IoT) cells, (50). The multiple carriers comprising a respective cell specific anchor carrier having NB-IoT sub-frames allocated for the transmission of mandatory information related to the functionality of the specific cell. The method comprises scheduling (S1) at least two cell specific anchor carriers using time interleaved transmissions that enables NB-IoT sub-frames belonging to different cell specific anchor carriers, and being allocated for the transmission of the mandatory information, to be transmitted at non-overlapping times. Also disclosed is a network device configured to perform the method and a computer program which when executed schedules at least two cell specific anchor carriers using time interleaved transmissions that enables NB-IoT sub-frames belonging to different cell specific anchor carriers and being allocated for the transmission of the mandatory information to be transmitted at non-overlapping times.