Skyteam, if the origin/destination/stopover citiers are the same, you can change dates for a flat fee per change-- meaning if you change the outbound, then the following week you call to change the return, you have to pay the fee*2. :-/ Fees are waived for Platinums, cost $50 for base members and $35 for Silver or Gold.

Redeposit is only necessary if you are changing the cities (i.e. flying RDU--LAS instead of RDU-LAX). Changes to connection points do not require redeposit.