At this time, Apple has neither announced an "event", nor have they made any announcements concerning potential new models of iPad. As such, anything that you have may have seen mentioned in the press or non-Apple websites is nothing more than pure speculation.
Until (or indeed if) Apple makes public announcement, contributors here have absolutely no information or insight into Apple's future products or events.
As for the front-facing camera location, moving the camera to the long edge of the bezel will reduce flexibility for some users. As is, with the camera positioned on the short edge, an iPad can be oriented such that the charging port of the iPad is located either to the left or right of the screen when positioned in Landscape orientation. If the camera is relocated per your personal preference, this is no longer possible if the camera is to be useable.
Likewise, for iPad models that support the second generation Pencil (that docks to the long-edge of the iPad) moving the camera to the long-edge of the iPad bezel is an issue - as the camera will occupy the internal cavity that is used for the Pencil's inductive pairing/charging electronics.
You'll perhaps take note that the iPad10 that has a camera located in the long-edge of the screen bezel does not support the second generation Apple Pencil - and cannot be flexibly in Landscape orientation with the charging port to the left of the screen.
In summary, relocating the camera to the long edge of an iPad has many implications - and for some, in particular those that use an iPad Pro, this may not be a preferred configuration.