hello , i got R6 Deluxe from Microsoft Game pass , now that my game pass ended i want to purchase the ultimate version from Steam , i want to know is it possible to link my steam account to this Ubisoft account or cause i had deluxe version on this account i cant upgrade to ultimate version .
Hello @Traxex_Hunter welcome to the forums.
You should still be able to purchase the Ultimate Steam year 7 edition of the game, whether you have played the Deluxe version previously on PC, Microsoft game pass. We no longer offer upgrades of the game if you have previously bought another version of the game, so you would need to purchase the Ultimate edition of the game outright. Here is a link to the Steam store page, if you scroll down you can see the different versions available > https://store.steampowered.com/app/359550/Tom_Clancys_Rainbow_Six_Siege/: (https://store.steampowered.com/app/359550/Tom_Clancys_Rainbow_Six_Siege)
As for your Ubisoft Account, please connect your Steam account to your Ubisoft Account, by launching the game and logging in with the same Ubisoft details you have used for your Xbox game pass. To check your account details, and linked platforms, you can visit your account manager website here >
https://account.ubisoft.com/en-US/account-information
Hello @traxex_hunter yes that is correct, you should have all content from the ultimate version of your game, available in your PC version of the game on Steam, whether you have played another version or not 
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