No details as yet but this has been posted on the Perth Military Modelling site. https://www.perthmilitarymodelling.com/newkitnews/hobbyfan.html
Note: Hobby Fan are the parent company of AFV Club. If you are having problems finding where Hobby Fan items are sold, any shop which stocks AFV Club kits should be able to get Hobby Fan from the same distributor. Some shops don’t carry stocks of Hobby Fan due to the cost factor but should be able to obtain it.
Update 27th March 2018: The Missile and launcher is now appearing in the shops and on-line. No sign of the tractor as yet.
For anyone wishing to find out more about the HAWK check out this link…
Dutch master modeler Wim Vink scratch built the whole set up in 1/32nd scale many years ago and posted some excellent info. Plenty of info on other modern US Army vehicles there too.