Ask the listing agent for the effective date of the pending contract. This date will go in the first blank.
Your client’s decision about the length of time he wants to stay in a backup position will determine how you fill in the last blank in the form. Some backup buyers may want to have their contract terminate within days if the first contract doesn’t terminate early, while others may want to retain their backup contract rights until after the last possible date that the pending contract might close. If your client wants his backup contract to last until or beyond the pending contract’s closing date, you can also ask the listing agent to provide the pending contract’s closing date.
Remember to tender the termination-option fee with your buyer’s backup offer if he wants an unrestricted right to terminate his contract and has provided for that in the main part of the contract.