915. For the purposes of section 914, an arrangement under which the payment of an amount is made on the security of a right under the plan or which provides for the release or extinction, in whole or in part, of a right or obligation under a registered retirement savings plan, either in exchange or substitution for any right or obligation, or otherwise, except an arrangement the sole object and effect of which is to revise or amend the plan is deemed to be another plan substituted for a registered retirement savings plan.