I think when supah says 'TBC' they mean a zero-hour Pit Stop, as with Brussels last season and Sydney and Lijiang in UB.
What I think might happen:
Leg 7: NEL (6 to 6)
Leg 8: 6 to 5
Leg 9: 'The next leg starts right now, here's your next clue.' (5 to 5)
Leg 10: 5 to 4
Leg 11: 4 to 3
My main issue with a zero-hour rest in Tanzania is that TAR generally avoids having African legs take place in the evening, which is a possibility (we don't know when they arrive in Tanzania, how they get around, or what tasks they'll do). Brussels was fine to have a zero-hour rest since WRP doesn't particularly care about people driving in Europe, while Sydney and Lijiang each had forced long-distance (overnight) transit to get Phil and co. ahead of the racers.
Admittedly, we don't know if the second Tanzania leg is in or around Arusha, nor do we know where the Indian legs are beyond Kerala so this is all presently spec. I do think a long-distance train ride or flight to a different location entirely would give production the jump they need on teams (especially if it's to somewhere like Mumbai, Delhi, or a city close to either of those two, where they can more easily get to Osaka).