Adding time near the beginning of a motion study

Does anyone know if it is possible to 'add time' at a point part way through the timeline of a motion study? I'm trying to slow down one particular section of the animation, without having to shuffle all my keypoints along one by one - they have all be carefully set up and syncronised, and it always seems messy to have to move them all in order to add a few seconds near the beginning.

Any ideas? Thanks if advance.

Tom

SolidworksMotion Studies