Thx. So mileage upgrades are not necessarily available even if seats are available. In summary, I may never be able to use my companion pass and if I do, it will likely arrive at 1:00 am. Also, I cannot necessarily use my miles to upgrade to comfort+. If I just use my miles to book, it’ll cost me about 180,000 miles for a cross country trip. Well it was a good experiment I guess but I have long loved Southwest for their straightforward policies and low fares. So I’ll likely ditch the Delta card. Thanks for replying and stay safe.