PitR's
What he actually said was "My only concern is that it will attract too many flights in the near future, which will result in longer queuing times", which is not quite how you described his comments.
I'm sure Stobarts are well aware that they must maintain the ease of use aspect and won't be looking for additional flights at peak times until the terminal is doubled in size. There's obviously plenty of capacity still off- peak so that's where any growth in flight numbers is likely to be seen next year I imagine.
LTNman
I've done a little research on pax numbers on the AMS route and it certainly does seem to be true to say that some flights have experienced very low figures in the past week, although I haven't been able to obtain the exact numbers. It will be interesting to see the September CAA stats in 10 days or so.