This change is long overdue, as there was a severe loophole of exposing personal data, as under:

1) If you know when someone is travelling, you can start the OLCI process with name and flight number to get the PNR.
2) You can enter surname+PNR into website like checkmytrip.com and get the e-ticket number and all associated details
3) Using booking number obtained from step 1, and e-ticket number from step 2, you can login to MMB and change anything and also look up passenger information from APIS like passport details, address, etc.

This loophole is now closed.