So seeing this on the upcoming improvements thread I gained hope that my Season Pass would give me access to the DLC on both my 360 and One. I have a games disk of Ghosts for both consoles and regularly play on both consoles.
"Additionally, for fans looking forward to the Call of Duty: Ghosts Onslaught DLC Pack, please note the following with regard to transferring DLC from Xbox 360 to Xbox One. If you are a Call of Duty: Ghosts DLC Season Pass holder, then your Onslaught DLC Pack will carry over from Xbox 360 to Xbox One. However, if you are not a Call of Duty Ghosts DLC Season Pass holder and purchase the Onslaught DLC Pack individually, it will not carry over from Xbox 360 to Xbox One. Currently, Microsoft only supports DLC transfer between Xbox 360 and Xbox One if you are a Season Pass holder. However, the Call of Duty: Ghosts Onslaught DLC Pack will carry over from PlayStation®3 to PlayStation®4 whether you purchase it individually or get it as part of the Call of Duty: Ghosts DLC Season Pass."
On my One it says my Season Pass is 'purchased', on the 360 it wants to charge me 4000 points or $64.95 when you go to purchase. (That's Aussie price for all those Americans thinking $50 is too expensive, try being here). Why hasn't it given me the Season Pass on the 360? There is no way I should have to buy two of them for the same family of consoles and the same gamertag.
The Season Pass upgrades from the 360 to the Xbox One for free. Unfortunately, not the other way round.
So - if you purchased the Season Pass on the X1 you can not play it on the 360 unless you purchase it again.
It is the way microsoft designed the process to work - as an upgrade.
I agree that it is silly not to work the other way. But that is just the way it works.