So my experience on a domestic AI flight from BOM with a name mismatch. The name on my ticket was Gates / Piper Dawn Mr instead of GatesDawn / Piper Mr.

• At check-in there was a name mismatch error when the check-in agent tried apply my SQ *G FF# to my reservation. When she saw my *G status on my SQ mobile app she had no problem priority tagging my bags. She could not issue lounge passes though or add my SQ FF# to my reservation. I could have left it at that and visited the Adani lounge with my PPs or CCs since they merged the lounges and credit the miles to my AI FF#. However, I decided to push, to see what would happen. I had plenty of time to spare. So I explained the name mismatch issue to the agent and asked her help to fix it.
• The agent took my case to her superior who sat the start of the AI checkin-in island and superior called me over. I explained my issue to the superior. She told me that she could change my name only once in the system and if it didn't match even then there would be absolutely nothing she could do. Now I was inside her cubicle so I was looking at what she was typing on her terminal. Stupidly, I forgot to remember the command she issued to change my name. It went like "somecommand gatesdawn/piper mr". And the name change was done. The terminal displayed:

• The change was done and the system accepted my SQ FF# and showed my *G status.
• The superior then also told me I was lucky she was there because she was the only person there who could have helped me and if she was not there I would be SOL.

So it does look like absolutely any kind of name change can be done when the ticket is in airport control (or possibly even by phone/city office agents earlier) if they have the authority to do so.