Sorry to bump a 2 month old thread, but it was the best search result I could find...

So I'm a brand new DL flyer. After about 165k UA/CO miles flown this year, I find myself needing to be in Atlanta every week for the next 7 months, so I am in the middle of a platinum medallion status match challenge. All I care about is schedule and nonstops, which is why I'm switching to DL for the immediate future, and domestic upgrades, free or with miles. I have basically no interest in international award travel, at least not through SkyTeam. I have lurked in this forum for a few weeks but have not found answers to a few questions on mileage upgrades:

- If there is no G inventory but I want to call in for a mileage upgrade, can I waitlist?
- If I do waitlist and it fails to clear prior to the complimentary medallion windows, do mileage upgrades have priority over the complimentary upgrades?
- If there is priority for mileage upgrades on the waitlist, how close to flight time can I call it in? Inside 24 hours?
- Any tips for upgrading SFO-ATL-SFO on the Monday AM/Thursday PM schedule? I am batting 2 for 6 in my first 3 weeks of flying on Delta