No, nothing that I have heard. As far as I am concerned there has never been a problem with Fisherman's Gat. I know we were discouraged from using it but its amply wide and there is plenty of room outside the buoyed channel for us - except perhaps inside the Inner Fisherman.
We are doing an article (amongst lots of other things) in East Coast Sailing on the London Array for May which is tomorrow! (Unlike other magazines like Sailing Today who published their June Edition last week! Why?). Colin is planning to have it available in the morning because its unusually going to rain in the morning and he cannot carrying on with his fitting out. Sorry drifting there.....
Foulger's Gat is not exactly shut. They have lifted the buoys of course but then marked it with an avenue of turbines. If they are working adjacent to the Gat then the exclusion zone that accompanies such work does shut it off - definitely. Bear in mind that there is a lot of diving work going on putting cables in so you might not see something and there is a lot of sundry cables and anchors around the Gat not necessarily related to the work schedule. Always call the Mary Ann 1 - the Guard Boat and they will advise.
We are putting a PDF download of the London Array article on the East Coast Sailing web site downloads page and that should go up tomorrow. I have also done a couple of new sectors for Foulger's Gat avoidance which link into existing sectors in 'Crossing the Thames Estuary' so you can add the dogleg to Fisherman's into your planning. Those sectors will be in a free supplement on my web site in the morning but I am afraid you do need the book to link into the other sectors.
Back specifically to you Bob. The London Array normally publishes its week's work schedule on a Monday and include it in the NtM pages during Monday evening. As luck would have it, on the Monday in the third week of May, I will have to be driving to Hampshire to earn some meagre sailing vouchers and so I was going to be a day late. I can probably post here on the Monday evening if there is specifically any Foulger's Gat work - but then diverting to Fisherman's Gat coming from Burnham adds less than a mile and a half to the journey - less if your draught enables you to cut inside the Black Deep No 8. One cardinal rule - don't go against the tide in the Black deep doing this dogleg; there can be tides running at up to and over 2kts on springs.
There - nearly written the article again!