Thirteen ibis observed from Milton this evening

Annie and I watched from behind the Milton Brewery this evening. A couple of grey wagtails came into roost along the stream, just as they did the previous evening at about 1700 hrs. We waited and eventually 13 ibis came over, following pretty well exactly the same flight path as last night but a bit lower and 10 minutes later (1725 hrs). We watched for several more minutes until it was becoming a bit too dark to see well but the other 10 didn't appear. So it seems that the flock has now split up. Did the other 10 come into roost from a different direction we wonder? Hopefully other observers will have seen them somewhere.