Typically it's 6 months after the kits go up for sale. If you're wondering why... it's because a company has to recoup their investment on each new product that goes to market. FT is truly amazing that they freely give the plans away like they do.
Ya I've seen plans come out like a week after the speed build kit but I'm not in a hurry to build this plane anymore as I've got the corsair all cut out and ready to build.