Advanced Classes and Roles:
The roles that you are allowed to queue for in Group Finder are based on your Advanced Class and not your skill point allocation. For example, if you are a Jedi Sage you can queue for both damage and healing.
Once you launch Group Finder, you can limit yourself to a specific role if you so choose. You can also queue for both of the roles that are available based on your Advanced Class. However, you are more likely to be assigned to the less common roles (tanking or healing) than to damage.
When Group Finder successfully matches you with a group, the icon next to your name will display the role you have been assigned. However, Group Finder does not automatically allocate points in your skill tree based on the role selected; you must change your allocations manually if required. For example, if you are a Jedi Sage that is allocated to a damage tree and you are assigned to a healing role, you will have to travel to the respec vendor and reallocate your skill points before you travel to the Flashpoint or Operation.