So we could expect the iPhone 12 SE to perhaps use a single rear camera and come with a near bezel-less 5.4-inch display, but without a particularly high resolution and potentially an LCD rather than OLED screen. This would help keep the production costs of the iPhone 12 SE down.
The whole point of the release of the iPhone SE was to provide an iPhone with a Home Button for the huge number of customers that won’t buy into the Jony Ive fiasco (and which Apple is now fixing). So, there won’t be a 12/full-screen version of the SE lacking a Home Button. There will be an iPhone SE Plus, for those that prefer the larger screens, and there will be an iPad SE for those that have held on to their iPads all this time.
These are being released to stave off existing customers from looking elsewhere, ie at Android (seeing as how the dumb Home gestures are identical to Android’s - great job, Jony, at passing away differentiators). By 2022 we will get models with virtual Home Buttons and software that will also implement that on legacy iPhones going back to the original iPhone X.