(Pocket-lint) - OnePlus is likely preparing to launch the OnePlus 7T Pro, but a new leak has us wondering whether another device is also coming down the pike.

Reporter Evleaks shared some sketches of what some believe may be the OnePlus 7T Pro. Redditors have suggested the sketches are a couple weeks old, but we can't find evidence of them elsewhere. Either way, they aren't well known, and they give us more questions than answers.

First, the sketches show a phone with a huge circle on the back for rear cameras. We can also see buttons and possibly OnePlus's alert slider on the sides. As for the bottom, there appear to be cut-out holes for the speaker and USB-C port.

We also have this image of some prototype OnePlus device from last year (notice how similar it looks to the phone in today's sketches):

So, why are all these leaks so perplexing? Let's go back a few weeks...

OnePlus recently confirmed it is planning a second 5G handset for the fourth quarter of 2019. It didn't say which device that would be, but OnePlus debuted the OnePlus 7 Pro 5G, its first 5G smartphone, just lay May. Now, keep in mind OnePlus also tends to push out a mid-cycle "T" device every year. For instance, OnePlus 6T debuted about six months after the OnePlus 6.

Sprint also recently revealed it'll soon carry an unnamed 5G device from OnePlus. (Sprint's 5G network is live in five US cities and is expected to expand to LA, NY, Phoenix, and Washington, DC.) Sprint said OnePlus' new 5G phone will be the fourth 5G device it carries. Neither Sprint or OnePlus has said much else about this device, but we can't help but wonder if it's part of an all-new phone range.

Sure, these sketches mostly likely depict the rumoured OnePlus 7T Pro that's been pictured in leaks, and it's probably headed to Sprint US as a 5G device. But, the thing is, the design of the phone in the sketches is very different from the OnePlus 7 Pro, which has a triple camera setup arranged vertically. Again, the mystery phone in today's leak has a large circle on the back instead.

It would be very unusual for a 5G-enabled OnePlus 7T Pro to look so drastically different from the still-new OnePlus 7 Pro.

Writing by Maggie Tillman.