I can’t find this answered anywhere else but I ordered from Adorama on 9/18 so all my invoices say 9/18 but they shipped it to me a week or so ago and before I register it I want to verify that it still qualifies for step up. Thanks

Contact EVGA directly ... seems your past the 90 day window - the way I understand it.
 
Your seller could have given you an invoice with the actual purchase date when they shipped it .... maybe not if you prepaid ?  do not know
 
That would be between you 7 the Retail outlet you choose
 
You should register the new card for warranty ... if you ever need an RMA - best to have it registered & the invoice uploaded - while you can easily find it

Captain_v_neck
You’re past the 90 day mark from the invoice date. However, the step Up page states that you can buy some extended warranty and it will grant access to utilize the step up queue.

That's not how it works. 
 
After you receive your card, you have 14 days to register it to access the "Step Up" perk at no additional cost. If you don't register it within the 14 days after purchase, you may still buy an extended warranty up to 90 days after purchase that will enable you to use the "Step Up" perk again. In either case, once 90 days passes from the date of purchase, the "Step Up" option is no longer available regardless of whether or not you've purchased the extended warranty. So if you waited for example till the 89th day to purchase the extended warranty, that would NOT give you an additional 90 days from which to Step Up. You will have 1 day in which to Step Up since you are still bound by the original 90 day window. 
 
So no, once you're past the 90 day window you can't just buy an extended warranty and then be able to Step Up. The ability to even purchase the extended warranty is removed after 90 days regardless. 
 
As for the OP, I'd call EVGA and see what they say. As I understand it if you paid for the card on the 18th of September that's what will show on your invoice and that will be the date from which your 90 day window started.