Access: Control Autonumber Update?

I have a record creation form connected to a table in the usual Access way.

As expected, as soon as any field in the form has data entered in it a form dirty event occurs and the Autonumber primary key is automatically created for the new record.

Once the new Autonumber is created, there is no “going back”. If the form data is discarded, the Autonumber assigned is no longer available for use in the table.

I would like to control when the Autonumber field is updated so that a new Autonumber is generated if and only if an explicit save of the form data is executed by the user.

It looks as though the only way to achieve this is to use an unbound form and fields and DAO or ADO methods in VBA.

Any other ideas on how to interrupt the automatic assignation of Autonumbers (on a bound form)?