Composer Steve Mackey, of Princeton, New Jersey, understands that feeling. The performer who commissions it, does the work, gives the premiere, should have that period. Maybe they'll get gigs based on the new piece. Most commissioning contracts for chamber works cite a period between one and three years. The period usually begins with the first performance, so long as the premiere comes within a reasonable period after delivery of score and parts.
Some contracts just start the clock on delivery.
A contract can specify any set of conditions. The key is to have it in writing. You've just got to have it. One might assume that composers and publishers always want a shorter period or none at all, but it is not really that simple. There are eight or ten questions that need addressing in all cases, but the answers are not the same.