Apparently, this is going to be a limited release, for Famima Dot Com's advance sales of tickets for Macross Frontier Theatrical Version. Limited in production, you need to pre-order this kit from the website if you're interested. The price is 6,025 Yen (inclusive of tax). More information will be released on Famima Dot Com soon.
YF-25 is a unit newly designed by Shoji Kawamori-sensei, which is the link between YF-24 and VF-25. It features a new head and canopy design, with seating built for two. It's capable for the transformation between Fighter, Gerwalk, and Batroid modes.
Information and image from Macross Frontier's official site.
