The legal machinations around Xbox's planned acquisition of Activision continue apace, with the latest update coming direct from Xbox head honcho Phil Spencer in the form of a new open letter.

While much of the content isn't breaking new ground, he once again affirms that Xbox plans to bring Activision's most famous franchises to its Game Pass ecosystem.

That includes Call of Duty, Diablo, Overwatch and more, and reinforces the thinking behind Xbox's purchase in the first place. However, Spencer also again says that Xbox is "committed to making the same version of Call of Duty available on PlayStation on the same day the game launches elsewhere".

While this is only underlining what Xbox has said before about the massive shooter franchise, the more it reiterates that position the more likely it is to be held to it in the future, once any existing legal obligations have expired.

If the timing on this letter feels a little random, it's worth bearing in mind that in the last 24 hours the UK's Competition and Markets Authority has spoken out to confirm that it will be conducting a deeper investigation into the buyout's competition implications.

That announcement included the statement that the CMA is "concerned that Microsoft’s anticipated purchase of Activision Blizzard could substantially lessen competition in gaming consoles, multi-game subscription services, and cloud gaming services", which won't make great reading from Xbox's point of view.

Exactly how this will all play out now is a complicated question, with regulators around the world queueing up to get responses from Microsoft and Xbox, but it's at least somewhat heartening for series fans to know that any outcome now seems likely to guarantee more Call of Duty on the PS5 and PS4 down the line.