Slitherine

When a unit charges it may reduce it's frontage by one file ( if need be ) . is the manoeuver done BEFORE the charge or after contact ?

In some cases, if the manoeuver has to be done before, it will be ilmpossible due to friendly units in the way but wiould be possible after contact is done a few MU further away as space will then be enough .

based on page 54 "to pass" I would say the bases fall behind at the point of needing to fall back.