Good luck, I hope it works out and that you don't need to change your plans.

It will come down to any restrictions on the ticket ie the fare rules. It's impossible to guess, but for many tickets the return portion can be changed without a fee provided you don't go outside the original rules (ie a one month return must be used within a month) and there is availability. Your agent should be able to tell you the rules, or if you booked online they should have been available then. If you have anything you can cut and paste here, then we could take a look. EVA/US should also be able to tell you.

EVA won't impose any additional fees other than those stated. So if the ticket can be changed without restriction, you should be able to just ring them up. From Taiwan you dial 02 2501 1999 (normal rate call). Hang on for the English message. They'll do it over the phone and that's that. It's 7 days a week, but not 24 hours. In fact you can ring any EVA office to make these changes - and during some of my nocturnal moments I've phoned EVA in other time zone just to get a booking done. Hotels will also take care of these things too, but better to do it yourself in case there's a decision to be made. Generally I've found Elite class the most difficult availability wise, though business class (Premium Laurel) can also fill up.

Seems your daughter will be starting her new life as an EVA flyer... a great start!