Answer: Most grape vines respond favorably to pruning. If you need to cut it back to repair or replace the trellis that is no problem. If you do it now you may sacrifice any grapes this season. The best time to prune it back is in late winter. Here are some instructions you may find helpful. (You may need to cut and paste the complete url into your browser ot make it work correctly.)
Good luck with your grapes!
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