My new boots have a slightly smaller BSL length. What adjustments must I make to all my bindings that were configured for a 317 BSL? Please advise.
You need to adjust forward pressure, i.e., move heel piece forward by 2mm, assuming it was set correctly for your old BSL. Various bindings have different ways to adjust FP.
You may not need any adjustment with only 2mm difference, but look at the forward pressure indicator and go from there.