No, not heard a single rumour.
It would be a month since the tour ended and Glasto kicks off. I doubt, unless they have other plans here they would stick around that long for one set there.
They already played Glasto a few years back in the comedy tent. Not sure if they would be worried about heading there again.
And lastly, I ain't into lobbying or petitions for this sort of thing. If the guys want to play it, or are invited, they'll do as they want. Either play it or not