Can you see if you can be put onto CM’s PTY-SFO flight instead?

Unsure on what day or time you are travelling at, but it might work out better (and cuts out 1 connection) - actually I see you are on UA283, so the timing works out perfectly if they can put you on CM208 PTY-SFO instead. Your connection in PTY should be pretty painless, deplane SCL flight and walk to gate for LAX/SFO flight. Bags should transfer automatically

2* flights to SFO per day by CM. One arrives at just after midnight. The other just after 3pm

*This is summer schedule, it will drop to 1.5 flights per day after the summer