Form = will have PAST PARTICIPLE
By this time next year, Max will have finished serving his jail sentence.
Before the football season starts, the players will have practiced together for almost two months.
By the time we get to the auction, they will have sold all of the good stuff.
The future perfect is used to express that an activity or condition will finish prior to a particular point in time in the future. The particular point in time may be marked by a time expression, action, event, or condition.