Yes, I did went expecting the same. But they said missing siblings cannot be added until any one of the sibling renew NIC and during this renew they will add the missing sibling. This way the system will be updated and I'll get my complete FRC showing all siblings.
you must understand that they received an all time high applications. If they could predict every process and decision i am sure they will tell you your decision will be ready by a certain time. Some applications take longer and require a much detailed assessment than others. it is clear they work on priorities as well. so really the might or might not give you a decision within the said time frame or even they might surpass the given time frames by months.