Long story, basically they will become championship use only, still road legal but will only be sold to race teams and no longer available to the public like they are now. You will probably find people on ebay selling them if they can get them but people like us at Camskill and various other online places won't sell them.
Same goes for Yokos version and anything semi slick kind of tyre.
Tyres with a full tread pattern will be ok though, like RSRs, R1Rs, AD08s and Kumhos equivalents.