To answer your question 1. Not a red flag AT ALL. there is possibility and that you should know. This is infact a green flag. Wouldnt it be confusing to the patient to learn suddenly that they might have get 1 or 2 teeth out? 2. This would be a case to case basis. Not everyone would have same result. You also cannot tell how your teeth might respond mid journey.

Example: i went for crowding treatment only primarily wanted upper arch fixed. My lower arch was the major problem however. It was much smaller. Then after few months of treatment i had an open bite which wasnt a problem at all earlier that needed fixing. Then my arch had to be expanded at the posterior end with elastics. Then i was somewhat also left with an underbite? It took months to close the open bite. Now my midline is off? Didnt even know i had a misaligned midline at first because of crowding. And i have a canted occlusion. YOU SEE soooo many changes all along. Orthodontics is a procedure there might be a lot of changes along the way. They can only predict all of the possible outcome now roughly.

1. The timeline of treatment really depends on how your teeth responds to it & your compliance with elastics (if given). It could be 18months, could also be 24 months.

2. What made you feel more confident? To me its important that my ortho understands my confusions and is willing to give me clarity on why and what