I have a form with a subform, linked via bidirectional lookup so I can see or modify the associated ID's.

i.e. The Form is for each Contact, with a Subform listing Phone Numbers associated with that Contact. Each Phone Number has a field showing the ID(s) of the Contact(s) associated with that phone number, so I can lookup both ways. This works fine.

Now, I want to create a new Contact, and script to add a link back to a default Phone Number (i.e. all colleagues in the office have at least by default a link to the Phone Number record for the main office phone number). However I want to do this on creation, so the user adding the Contact can view and edit the phone numbers as part of creating the Contact, and perhaps remove the office phone number at this point if it is not relevant to that Contact.

However, until I have saved the new Contact, as far as I can tell, the new Contact has not yet been provided with a unique ID. So I can't link the Phone Number back on the subform. 

How can I achieve this at creation time? As I can't add subform rows programmatically, it seems like I am stumped either way.

Thanks,

Jim