The next iPhone will likely have a USB-C port. They couldn't have changed the lightening port on the iPhone after only being on the iPhone for a single generation.
You think they're going to ditch lightning after everyone buys a bunch of accessories? They could, but I doubt it. What would switching to USB C do for Apple?
They're not about to switch to USB-C on mobile. They've been doubling down on Lightning recently with the Apple TV remote and the new Magic peripherals.
If you're going to piss people off by removing the headphone jack, you don't do it again by changing ports next year. You tear the bandage off in one go.
Yes, I mean it exactly like that. Apple could and would switch if it provided them significant benefit (smaller, more robust connector, ability to make the phone thinner, new capabilities). I don't see that USB-C provides them with anything except a loss of control over the connector and a bunch of annoyed customers.