Disable process for an Unused Operating Unit

Hi All,

As per Business requirement, Wants to Shut down the one of the Operating unit to restrict the transactions flow in to GL and This should not prevent the period closer process in any other Operating Unit which is sharing same Ledger.

Business want to start this activity Module wise, initially want to stop Accounts receivable transactions(Both Scheduled & Manual) from the current month.

As we are using  Revenue Recognition process - revenue recognition unprocessed transactions which are already created in the system.

Please provide the process steps to disable the same ?

A quick response would be highly appreciated!