UFO witnesses the Grockle Exodus

Hooray. The Grockles are Going.
This twitty grockle pulled out across the road and the tractor was forced to slew to a halt. I'd got my camera for blipping so I clickt the twit. Never saw the UFO at all. Hmm. Speck of dirt on the camera? Nope; next shot was OK. Leaf on the windscreen? Nope; too perfectly symmetrical. Hallowe'en approaches... maybe it's the witchy transport for the 3rd millenium... ;-)