Ultimate pass code was not accepted for sixth plan Spotfiy 6 month for free plan.

Spotify offer is only available in certain regions, specifically usa and uk, I think, and there are other eligibility criteria, which can be found at the link below

Spotify offer faq

Also spotify is not only limited to uk and usa only GEOIp locked

But ONLY new accounts.

You won't pay £10.99 for the entire 6 months.

Assuming you got a 6 month code for normal Game Pass yes? By upgrading to Ultimate, you pay for the Ultimate for the first month (£10.99)...however, the 6 months of Game Pass gets converted to Ultimate, so you end up with 7 months of Ultimate:

"When you subscribe to Xbox Game Pass Ultimate, we’ll apply any prepaid time you have on Xbox Live Gold, Xbox Game Pass, or EA Play subscriptions toward the Xbox Game Pass Ultimate plan at the current conversion ratio, up to a maximum of 36 months. Prepaid time conversion is final, and ratios are subject to change."

https://support.xbox.com/en-US/help...age-subscriptions/xbox-game-pass-ultimate-faq

So you get Ultimate for less than the upgrade cost: £3x6=£18 vs £10.99

Hi There,

Purchase of Ultimate plan automatically upgrades your existing Xbox Live Gold or Xbox Game Pass membership(s) to Ultimate at a conversion ratio each based on days remaining. Therefore you would have 6 months of Ultimate.

Unfortunately once you upgrade your Gold membership to Ultimate Game Pass, you can never revert your account back to Gold. It is a decision that you need to make sure that you want to do. I actually earned a free month of Ultimate Game Pass that I am never
going to use because I read the fine print stating what I covered in the beginning. I have two years of Gold membership which would only be 8 months of Ultimate.

Purchase of Ultimate plan automatically upgrades your existing Xbox Live Gold or Xbox Game Pass membership(s) to Ultimate at a conversion ratio each based on days remaining. Learn how this works at www.xbox.com/gamepass.
Future code redemptions are also subject to a conversion ratio. Conversion ratio subject to change. All conversions to Ultimate are final: Once converted, you cannot re-convert your Ultimate membership back to a previous membership. Maximum 36 months of redeemed
Ultimate per account at a time, including any converted time from Xbox Live Gold and/or Xbox Game Pass (for PC or console).

After you join the Xbox Game Pass Ultimate plan, you can continue to redeem Xbox Live Gold and Xbox Game Pass codes. These codes will automatically convert to Xbox Game Pass Ultimate at a ratio based on the ERP (Estimated Retail Price)
of those codes.

[table][tr]1 month of Gold[td]20 days of Ultimate[/td][/tr][tr]3 months of Gold[td]50 days of Ultimate (1+ month)[/td][/tr][tr]6 months of Gold[td]79 days of Ultimate (2+ months)[/td][/tr][tr]12 months of Gold[td]4 months of Ultimate[/td][/tr][tr]24 months of Gold[td]8 months of Ultimate[/td][/tr][tr]1 month of Xbox Game Pass (Console Games)[td]20 days of Ultimate[/td][/tr][tr]3 months of Xbox Game Pass (Console Games)[td]2 months of Ultimate[/td][/tr][tr]6 months of Xbox Game Pass (Console Games)[td]4 months of Ultimate[/td][/tr][tr]12 months of Xbox Game Pass (Console Games)[td]5 months of Ultimate[/td][/tr][tr]24 months of Xbox Game Pass (Console Games)[td]10 months of Ultimate[/td][/tr][tr]1 month of Xbox Game Pass PC Games[td]20 days of Ultimate[/td][/tr][/table]