We have a master contract associated to a contract OS type order

what is the system impacts of changing the supplier# on the order header on Master contract (OM)types in JDE. What impacts are there if we update the Supplier# on the Master Contract what will be the impact to the Contract OS types which have the Contract# and the Supplier # mismatch with the Master Contract. I am sure this will have some impact....Please advise...thanks I remember reading this that you cannot change the supplier# once the contract is saved. However the business wants to be sure