References to new iMac models have been discovered in the latest macOS public beta, once again fuelling speculation that Apple could be developing new versions of the device with Apple Silicon chips.

As spotted by 9to5Mac, the arrival of macOS Big Sur 11.3 beta 5 contained the codes for two new iMac models - 'iMac21,1' and 'iMac 21,2'. It's not thought that this is related to display size, and, rather, the year 2021. 

Interestingly, this also follows a report that surfaced back in January, stating that the two new iMacs with Apple Silicon chips had the codenames J456 and J457. This is something that 9to5Mac was able to confirm in the macOS beta. And, according to that initial report, both the 21.5-inch and 27-inch models will be updated at some point this year. 

Of course, this latest find comes off the back of Apple officially discontinuing the iMac Pro and some versions of the 21.5-inch iMac - another huge hint that an iMac with an M1 processor, or something even newer, will be landing soon.

When that will be is currently unknown, though our best guess would point to a potential Apple event in April, before more MacBook models with Apple Silicon launch in the fall. 

Either way, when the iMac finally does receive an Apple Silicon chip, it's also rumoured to do so with a completely refreshed design. Some reports suggest the new models - perhaps the very two outlined in this new macOS beta - will feature a look akin to the Pro Display XDR.

If Apple does indeed decide to mix things up, it would represent the biggest design change the iMac has seen in eight years - about time, we'd say.