Do we have to renew the default NTR number for sourcing contacts every 3 months?

Currently, you are able to upload sourcing contacts without NTR and UDB will generate the NTR. We are giving 3 months of expiry for this sourcing contact. Within these 3 months, you should be able to provide a unique reference from your system and not just the name, so we can create a NTR template for these sourcing contacts.