Game Rules Guide

Yes. Ask the Advisor to take a troop's attack or defense to a level, for example your Legionnaires' attack to level 3. The troop must be researched in that village. The plan lists the upgrade levels as one task, and adds the Smithy (attack) or Armoury (defense) levels each upgrade needs, because each upgrade level needs the building at least at that level. Upgrades run in the Smithy or Armoury beside your builders, one at a time in each, so they never hold up your buildings. You approve, stop or cancel the plan as you do for buildings, and with a Gold budget the plan can cover missing resources for an upgrade too.