Right of Abode (COE) from outside UK

Dear members,

I am planning to apply for the ROA/COE for my son, who was born in India. He has British citizenship through descent (I acquired British citizenship in 2016, my wife is on ILR). If anyone applied and acquired ROA/COE recently can you please share your timelines? Also, I'd appreciate if someone could share the answers to below:
- Is TB certificate necessary for applicants under 6 months old (i read in this forum that it is not, but the way i interpreted the policy was that applicants who want to visit UK for less than 6 months are exempted, no other exceptions).
- I am planning to take priority service, is it any good, has anyone used it recently (I want to be in the UK asap as my wife would be hitting the 450 day threshold soon).
- I read that walk-ins are ok at VFS, is that true? Has someone used this option? I will take the appointment most likely but in case I don't get an earlier date I might go for a walk-in.

Thank you.

Useful to look at the existing topics we already have rather than asking all to post timelines again.

british-citizenship/right-of-abode-with ... 23547.html

Thanks, however I was looking for the timelines for applications made from outside UK.
I couldn't find those on this forum unless i missed them.