Atmos Rewards Credit Card Bonus Offers & Eligibility Rules Explained

I was rejected for not having a banking relationship and not having a car or house loan. FICO is over 800. A month later I received an invitation letter from Alaska so I applied again. Again rejected. I then found the Barclay Hawaiaan card and was instantly approved.

It has been well-documented that Bank of America's approval process for this program is notably inconsistent and, at times, quite unpredictable. Hopefully, Alaska Airlines/Atmos will eventually partner with another financial institution. I guess for everyone they reject with a FICO over 800, they must accept two with FICO under 650.

So, to clarify my understanding-- I have had the Alaska Signature/ Atmos Ascent card for 20 months. I am flying more and very interested in 2 things: the extra bonus and perks from a Summit card. If I understand it correctly (because it is not clearly stated on either of their sites, nor am I getting good information from calling BofA or Atmos) I should be able to get the welcome bonus on the Atmos Summit even though it has been less than 24 months since I applied for the Signature/Ascent. Am I thinking correctly here?

I don't really want two visas to keep track of. Will there be any issues closing the Ascent after the Summit is established?