Can we update person number using HDL without effective start date

Summary:

We are doing a bidirectional integration where we are sending source system id of worker to 3rd party & pending worker hire date. In return, we will receive a new updated person number that should replace the existing person number using the source system id.

Now the issue is, for pending worker , the start date in per_all_people_f should be the hire date or date when that record became pending worker. But in the system when we check , the earliest effective start date is coming as the date when the employee had applied as a candidate, even when he withdrew his request. This is jeopardizing the integration design. Is there anyway we can update the person number WITHOUT effective start date & just source keys in HDL.