I believe you need to hold the card at least 6 months.
After I go through the link, it said I could upgrade my Delta gold card to HHonors surpass card. The DL Gold was applied last Nov when 75k came out. I accepted. Now the DL card logo was replaced by Surpass in the online account.
Funny thing is, I applied a regular Amex Hilton card in June and still keep the card open. Now I have both regular and surpass amex card.
Will report back if I get the upgrade bonus for the surpass one.