Will there be another 15% bonus mile sale soon ?

Hello
I can remember not too long ago , that if you bought Virgin airmiles , that they gave you 15% extra as a bonus . Just wondering if anyone knows if this will happen again anytime soon

Thanks

I missed out on this - wasn't organised enough !

They seam to do it 2 - 3 times a year so its just a case of keeping an eye out.