Hi Richard.
Glad you enjoyed your visit Richard. The only birds you appear to have missed were the Ringed Plovers.
The Oystercatchers and Redshanks only arrived back recently and the ever present 'Long-tailed duck' appears to like it here. Marsh harrier is regular now. The 2 Avocet you mention returned only today, so you may have been the first to see them. It was midday when any local birders saw them.
If your lucky you can see 80 or so Red-crested Pochard and a lot more waders later in the year so do come back mate.
Your right about this being a fantastic nature reserve. Luckily a few of us saw Sutton & Lound gravel pits potential as a nature reserve some 30 years ago and approached the RSPB to speak with Tarmac about restoring and managing the quarries along the Idle Valley as a massive nature reserve.
Unfortunately they had their eyes on what they thought was the bigger prize on the quarries along the River Trent at Langford.
Unfortunately leaving us with little option but to speak to Notts. Wildlife Trust to pursue the dream.
If only the RSPB had chosen the Idle valley we wouldn't still be stuck with old sad looking and badly maintained viewing screens, that 'Tarmac' paid for and erected many years ago and miles of badly rutted, boggy paths that are to be honest unfit for purpose.
With a million pound lottery grant you might think anything was possible but much of the monies has been spent on paths, infrastructure and facilities around the NWT office at the Retford end of the reserve and unfortunately little or nothing being spent on the main birdwatching areas closer to Sutton and Lound villages. As NWT don't really want to encourage birders here in case they upset the villagers. Can you believe? and that's the reason the paths are such a disgrace and why the old viewpoints have little or no usable seating.
Thankfully most of the habitat management was done and paid for by Tarmac Quarries well before NWT started managing it (Badly) but it should have been much better and could have been if only NWT's management had been stronger during these past 3 years.

(It only took them 3 years to put the new dogs on leads signs up, courtesy of our lottery grant)
Still awaiting a real visitor friendly facility centre befitting the biggest and best nature reserve in the county but that's another story.
Thanks for the kind words Richard. See you at Gib. and soon hopefully.