I have an upcoming FWA==>MSP==>LAS flight with a 35 minute layover in MSP. I have been monitoring the FWA to MSP flight every day. Today it departed FWA 5 hours and 5 minutes late, and landed in MSP 5 hours and 36 minutes late.

On the day of my trip, if before I leave the house I check the website and see that there is a multi-hour delay leaving FWA, what would be the recommended procedure? Should I call Delta and try to get on another flight? They have a FWA to LAS route that departs FWA a couple hours later than my scheduled flight. It connects in DTW instead of MSP. If they have open seats on that route, would they put me on those flights? Is it first come - first serve, so the earlier I call the better?

It may be relevant to say that I have have no status with Delta. I'm flying on Skymiles earned with my AmEx Skymiles card. I'm probably Delta's lowest priority customer. I'd guess that there would be higher priority customers making the same request for a change of flight.

If it is evident that you will miss your connection or you know for a fact that you will miss your connection because your initial flight is significantly delayed, DL is obligated to attempt to re-book you on the next available flight. If you check the website before leaving home and it shows that your initial flight is, oh say, 2 hours delayed and you only had 35 minutes to spare in MSP anyway, I'd call and request that they re-book you on the later flight through DTW, if there are seats available. If they can guarantee before you leave the house, at least you don't have to spend 2 extra hours sitting around the airport!

Two thoughts:

1) If the first flight is delayed such that you miss your connection, Delta will automatically rebook you. Of course, you might not like your new route, seats, etc, but they'll get you to your final destination. And depending on how serious a delay it is, you might be eligible for food vouchers etc. But, a good first step would be to know what your preferred rerouting would be, and have that info when you call them (should your flight be delayed). And, yes, in general, the sooner you call once you know there's going to be trouble, the better. Or go to the airport even since the gate agents are likely to be able to help whereas someone on the phone might not.

2) If you ask to get on another flight, they'll charge you $150 for the change fee plus the difference in cost of the ticket. Simply not worth it, I think, but that might depend on how vital it is that you get to LAS on time.

Also, it's not totally clear from your e-mail but it sounds like you might be on an award ticket (i.e., you used miles to get the ticket rather than paying cash), in which case your rebooking options are even fewer within a 72-hour window due to recent DL policy changes (you can read a lot about those changes elsewhere on FT).

Check on delta.com before you depart your house. If there is a delay of greater than 15 minutes you should be able to change your flights yourself for free.

Although be careful as some people have examined there options only to be automatically re-booked.

Not clear if you have status, but the Medallion line would probably be a big help.