1. On those routes, I don't know. I don't think of operational upgrades as all that common for PLT members -- I got maybe 1 or 2 a year.
2. If you're already Premier Executive or 1K, don't take the challenge! Show your card to an AA agent and get Platinum status on the spot. Do this before you leave on the 29th, so that you can get the 100% bonus on the entire trip.
3. Don't know.
4. AA does not give out system wide upgrades for PLT status.