This 100% true, but when I have a group and one person gets tired and decides to call it a day, you can use that person's now used MP to look for cancellations. When you find a good one, you can cancel the remaining group's FPs and change to the cancelled one that just came available. Note that the larger your group, the less effective this is because when you see a cancellation on the unused MP, that may be only for one person - but it may be for more. You do not know until you cancel the MPs for the remaining group.