I'm departing from LAX... my itinerary is Delta 7652 first to Seattle (but operated as a codeshare with Alaska Airlines #471), then onward to Beijing.

My first flight is a domestic to Seattle and the SEA-PEK international is the connecting segment.

Questions - since my first flight segment is domestic does the 90 min. domestic rule apply even though my final destination is Beijing?

My flight is Delta but it is operated by Alaska airlines... at LAX looks like they are in different terminals. I would check in at Delta (Terminal #5) and then go to a different terminal to catch Alaska (Terminal #6?) That seems really odd...I've never done that before.