I was in Winnat's Head on Friday night, and we noticed (it's hard not to notice) a significant boulder moving in the final choke below Fox Chamber, before the sump chamber (the choke with a handline in and the bold step onto a ledge, not The Slot). The boulder is well worn on one side so has clearly been part of the choke for some time, but it now moves freely and could block up the choke. A member of our party tried to bed it in place a bit better but no such luck, it just sent some sizeable stones falling through the choke and into the chamber below.
It doesn't look like the boulder will fit through the choke itself so if it wants removing to prevent it from causing any problems it will need slinging up and hauling out, or taking down to size. Some other significant-looking parts of the choke are also crumbling away around the rock's former position, so I don't know what the knock-on effects of the rock's movements will be to the choke in general, but I think someone with a better eye for this than me needs to take a look and size things up. In the meantime just be wary of the offending boulder! You have to slide across the top of it in the choke and if you knocked it over after you it would jam in the choke behind, and would be an awkward (but possible) lift to get it out of the way and back into a safe place above you, I wouldn't wish it on anyone!
In addition to this it also looks like there's been a fresh collapse right inside the entrance - there are a few more large, freshly scarred rocks on the passage floor, some piled up to one side, and a few more items of "archaeology" (old boots, tin cans, intact glass bottles) that I've never seen in there before. Does anyone know anything about this?