No support, you do get a refund just not a huge one so that building effectively is part of the game. If people were to have 80-100% refund on builds then anyone could switch builds on the fly and make the battle mechanics useless since everyone could counter each other at a quick rate. This game isn't about building yourself to adapt at any time, it's about building a style of play and knowing how to use it effectively.
If this is implemented into the game then player will have the urge to wait until a new event peeks it's head to fix their builds, so they be excited for the event to come.