Other North & South America Frequent Flyer Programs - Is TAM flexible in changing flights at the airport?

Just wondering if anyone had any direct experience in arriving at the airport and being able to get on an earlier flight if you are already confirmed on a later flight for the same day. I don't know if they are like some who are strictly by the book. THANKS!

last October I had a ticket on the 10 PM GRU-EZE flight.... due to some traffic god miracle, I was able to get to the airport in less than an hour, so I asked if I could go standby on the 7.30 PM flight, (I had checked-in luggage), they said sure, no problem! so I was able to catch the 7.30 and my bags also made that flight! :D

last October I had a ticket on the 10 PM GRU-EZE flight.... due to some traffic god miracle, I was able to get to the airport in less than an hour, so I asked if I could go standby on the 7.30 PM flight, (I had checked-in luggage), they said sure, no problem! so I was able to catch the 7.30 and my bags also made that flight! :D
Thanks! Especially since that's the exact route I am inquiring about! That gives me at least the knowledge that they CAN do it if they want too. Cheers :)

If you have one through ticket, e.g. international + domestic, they will usually put you on the earlier flight if there are seats without any problems.
If you have a separate nonflexible ticket , e.g. promotional fare domestic, they will want you to pay for the change.

If you have one through ticket, e.g. international + domestic, they will usually put you on the earlier flight if there are seats without any problems.
If you have a separate nonflexible ticket , e.g. promotional fare domestic, they will want you to pay for the change.
It's the latter: domestic discount economy on TAM purchased through TAM (GIG-GRU) connecting to business class international codeshare (GRU-EZE) on TAM metal purchased through LAN. I want to bump both up to earlier flights. Are you saying pay a fee for the change or the difference in fares (or both)? I was just planning to go to the airport and try my luck.
Thanks

What they told me was fee for the change + difference, exactly as per change rules. It turned out quite high, so I decided to wait. That was for a separate ticket. Many times I've had connecting flights (arriving from abroad and continuing domestic) and been able to fly earlier without paying anything extra.
Of course it doesn't hurt to try, if you arrive at the airport early.