Yup, that is relatively new. Pax from every airline (except BA!) can use any entrance. BA pax are now required to enter using the last entrance on the far right (number 3 IIRC?) as you drive into the airport. There is a dedicated BA x-ray machine there. That machine has special under/over 23kg labels too. So remember to keep a spare Rs 50 note discretely handy for the bag-tagger at the x-ray if your bag exceeds the limit, but make sure you avoid contact with the prissy ladies in the local BA uniforms!!