Moving between gameplay and single sequence

Looking for advice on the best way to set up the following:

Simple game involving 2 states.

  1. Default state when there is no user input is a long camera animation tracking across environment based on keyframed cinecamera in a level sequence.

  2. When there is an input (mouse movement/click/game controller input etc) then gameplay mode is triggered. If there is no input for a set time period, then the game returns to the default state of the long keyframed camera animation.

How to ensure that when an input is triggered, gameplay takes over from the same location that the animated camera is currently at? And when there’s no input, we blend back to the closest point on the pre-existing camera path.