Who is familiar with AT&T details -- pls help!

[westla7]

So, I have a question. My two family lines are NOT eligible for upgrade. But they've been since last September, they have low ETF.
Can I:
1) Get two new iPhones by adding two new lines
2) Move two numbers from existing lines to new lines
3) Disconnect old lines and pay ETF for them which are low
Sounds possible? How hard and how long will it take to transfer numbers from current two lines to those new lines?

Thanks!