I went for a walk in chew on saturday. It was raining pretty heavy but from what I could see the bottom boulders were no greener than usual. I could not see the Tank properly or anything higher.
I'm no Wimberry expert - but living that side of the pennines, its been dry - clear and cold... But... the greenness can be significant in winter from experience. In other words, no idea about the green - but the general connies will be fine...As nearby back up plans - been to Nont Sarahs? (Buckstones)... A burly 7A+ traverse/nose of Pig in a Pokey - and other harder variations can provide enough for a work out...? Slap bang next to the road too...