Keygroup and " Patched phrase" sample

Hi,
I was thinking sampling some VSTs and hardware that have evolving textured sounds. The best results are by sampling every key but that creates huge library . The problem with sampling eg one note per octave is that the speed varies so I was messing with the "Patched phrase" feature on keygroup samples ,since warping is not available
But the sample is locked on bpm , which is expected , but I can't find a way to edit the sample's bpm property once created . Is there a way to do it on hardware ?

I like to Assign a Sample to only Couple Octaves(Max) in a Keygroup, when I'm whippin up something. To me, Creating Full Octaves across the keyboard is Wasteful. Because whenever I load a Pre-made Keygroup program, I only use a Couple Octaves of it anyway.