From what I can see, this transmitter requires a PC for programming, which means yes, the mode most likely is able to be switched.
Models will probably be stored on the PC and not the transmitter, so no to the first question.
You'd probably be better off getting an FS-i6 or an FS-i6X rather than that transmitter to be honest. I don't have much experience with turnigy transmitters but I don't think I'd trust one much.
From what I can see, this transmitter requires a PC for programming, which means yes, the mode most likely is able to be switched.
Models will probably be stored on the PC and not the transmitter, so no to the first question.
I don't know if the mode can be switched. Contact hobbyking and they will let you know. It is available in mode 1 and 2 you just have to look at the transmitter page.