Yes, it's normal. How long it takes till your case gets allocated to a CO depends on how many applications have gone in to that branch just before yours, so the busier things have been, the longer the wait will be. Everything at INZ works by managed queues. When your ITA was received, it would join the end of the queue of other ITAs, according to the date order. Each Case Officer has a certain workload - a number of cases that are theirs to deal with. The newly arrived ITAs have to wait till one of the COs has finished with some of their cases, and can take on some more. When an ITA is eventually assigned to a CO, it will again join the back of THAT queue for the CO's attention, as s/he takes the top file, does what s/he can actively do, puts that file to the back, works everything s/he can on that case, goes to the next, and so on.