Yeah probably with the major redesigned iPhone next year. USB C will be more established in Macs and overall so it would be a suitable time. It could always happen this year but that would probably be a step too far after making people switch to lightning/Bluetooth headphones.
Yeah I know I think removing the headphone jack is a step too far there is no reason to do it. I don't think Apple actually want to do it they just feel they have to get rid of it due to the size of the port. Therefore they'll likely push wireless headphones due to compatibility.