Backwards Pass or not

[WVREF]

Something that came up one time, not a likely scenario but it did happen. Usually on this play if the pass is caught we relax because now it doesn't matter whether it was forward or backwards. Except it still might be important. If this is part of a double pass play and B interferes with the second pass it becomes very important whether the first pass was forward or backward. Forward= no DPI, Backward= DPI.