How Far In Advance Do I Add the M.E. To Ressie?

[annnewjerz]

I booked a room-only package for our trip in October and now that we have our flights secured, would like to add the Magical Express. Usually we do packages and add all of that stuff at the same time---so I'm a little confused about when and how I add the Magical Express to my reservation.

Can anyone tell me how far in advance this should be done, as well as where I can go (or who to call) to do it?

Also---we booked on Southwest and there is still the possibility of changing flights if a better one opens up. If my flight changes late enough that I already have my Magical Express tags, etc. how does that work? Do they need the updated flight information or will my luggage tags and confirmation still work even with the old information?

Thanks everyone!
Ann