I have traveled to India a number of times but this is my first time connecting from domestic to international in Mumbai. I have a few times arriving from international and stay overnight at a hotel then catch a domestic flight, which is a different story comparing what I experience below.
My entire connecting time is 2 hours and 20 minutes. Just list the number of lines you need to go through:
1. After arriving, the first line is to get a number in the arriving hall in order to get on a transfer bus.
2. the 2nd line is to line up at the "International Transfer" gate waiting for your number to be called.
3. the 3rd line is after the transfer gate open, waiting for your luggage to be scanned (first scan)
4. Then get on a transfer bus, it is not a usual airport bus, but rather a tour bus, which makes difficult to get on and off with bags. after about 12 minutes ride, you arrive at the ENTRANCE of the international terminal (note: not directly inside the terminal. The 4th line is to show you have a valid ticket and id to travel.
5. Then the 5th line is to go through immigration. Actually there are two lines for this but let's just count one.
6. The 6th line is to go through the security (second scan)
7. The 7th line is before you reach the gate, a US security check (third scan)
8. After the US security, you enter into a holding area with no chairs and wait for another 15 minutes, then you line up again, 8th line for boarding pass and passport check
9. If you want to count another line before boarding the plane, it is the 9th line!
In this entire process, the elite status is only recognized at the 7th line!
After I went through all this, I check the time it is 140 minutes total. Before I started the trip, I checked this forum and did notice there was one advice given to someone not to let an elder mother go through this transfer. After this I said to myself, no one should go through this, it is not a transfer, it is an adventure