Mine have got a bit hit or miss too - some days 2 eggs, some days 5, out of 6 that aren't away brooding, in obvious moult etc.
I think the thunderstorm the other day and torrential rain since has made the days quite dark by comparison to previous weeks so they may be reacting to that by not ovulating even if they're not in moult? In which case hopefully you'll get a few more eggs if the weather picks up again..