So I had two SDCs yesterday my original was LAX > JFK

I switched to LAX > LAS > JFK (10PM out of LAS) I did this at around NOON

When my LAX to LAS flight was boarding they told me i was standby not confirmed I should of looked at the ticket and didnt make it on.

So I wnet to the agents by security I think its gate 50 and she tries to put me on the LAX to San Diego flight and San Diego to NY.

But said the system wouldn't let her because the San deigo to NY flight was more than 3 hours away.

Why was the system able to put me on the LAS to JFK flight earlier but not the San Diego to JFK flight which left earlier than the LAS to JFK flight?

Was she mistaken when she said 3 hours? My guess was it was an illegal route even though she insisted it wasn't.

She also went as far as to say let me try putting you into Y to see if I can get it done and the system wouldn't even let her do that which made me think again it was an illegal route.

I eventually ended up getting on the 7:30 LAS flight and the 10PM LAS to JFK flight FC all the way!