Sorry--the last message was a mispaste.

I have 2 grapevines, one Bluebell and one Somerset Seedless, which I planted last spring on either side of an arbor. They're well fertilized and mulched but I didn't get to pruning them. Now the vines are at bud burst. Can I still prune them now without damaging the vines? I've seen online references to doing a *second* pruning at/after bud break; how about a first one?