Steam Collector's Edition Code Question

So I got the Pre-Order Collector's Edition from Steam. When I went to Mogstation I noticed a button for inputting info for Stormblood. I enter the Pre-Purchase Bonus Items first, lock in and got the O on the Stormblood Early Access, but when went to go enter the Collector's Edition code that button disappeared and where I look I can't seem to find a place to Register the code

This is my first time on Steam Pre-Order so I am kinda baseless on this events. Will I be able to add in my code on a later time such as on Release or did I goof and locked myself out of my Collector's Edition?

You'll likely be able to add the code in later. All of us who ordered direct from SE don't even have the actual game codes yet (only the preorder code) - at least not from the EU store - and I don't have anywhere to enter a full game code yet either.

If it's like Heavensward was (and it probably will be) there will be a huge ENTER EXPANSION CODE HERE button (it was giant sized) :D