#1 Yes you can move your online return to the Desktop program to amend. But I don't know if you can efile it since it's not from the same account you efiled the original return. But why don't you want to amend in your Online account?
To continue in the desktop version see this…….
https://ttlc.intuit.com/community/choosing-a-product/help/how-do-i-switch-from-turbotax-online-to-th...
#2 don't know
#3 don't know when. But if Turbo Tax has the 1040X available you can probably efile it.
