Overnight fans spotted that an internal alpha for the game was apparently uploaded to Battle net, Activision & Blizzard's PC service platform.
The internal alpha has the name 'Slipstream' and along with the alpha was a new piece of artwork, which you can see above.
It doesn't give away a lot, unsurprisingly, but some quarters have suggested that it's got a certain WW2 flair to it.
The new leak was also corroborated by well-known leaker Tom Henderson
For anyone confused it's worth reiterating that this is just a code name for the game and not the official title of Call of Duty 2021. For those who might remember, the code name for Call of Duty Black Ops: Cold War was 'Red Door', which was a reoccurring theme throughout the main campaign.
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