Well, frankly, I really don't recommend it. At the time of writing, the river has reached 2 metres! Only 10 times the usual level, so the chances of fishing for anything except floating debris are just about nil, but I'd love to read your Catch Return if you do go.
I think we can forget about fishing there for a few days at least, as it will be like Brown Windsor Soup even when it does eventually go down.
Don't forget that we do have a special extension to fish Beats 3a,b,c until the end of November, not that it'll be worth much if we continue getting rain like this, but you can always apply for a Winter Ticket and carry on Grayling fishing through until the end of February.
If we do ever get down there this month, I would recommend something Pink (on your nymph that is), perhaps combined with a heavy nymph if possible. A few people have found the famous Grayling Bomb quite effective for Trout; that's the bright pink shrimpy one with the double bead head. It's worth experimenting with the heavy nymph (I like to use a large jig tungsten bead if possible) on the point or on the dropper, for different effects. I also prefer contact nymphing where possible, using a nymphing line, but a long tapered leader is probably fine, and casts better.
Frankly, I've found the few Grayling I've seen rather hard to tempt this year, even to my Double Badger, but maybe the cooler weather will make a difference. Please keep your Grayling Catch Returns coming in even after the end of the month, as it's helpful to know how they're doing, and what works on them.
Meanwhile back to tying more flies, reading more fishing magazines, or processing the season's Catch Returns - what a choice.