@Kafka I think there may actually be more to this.
While playing around with teams in Delves (the Fang Moor Faction Event), I noticed that my hero’s class was displayed differently depending on whether I selected from the Weapons list or from my Team.
This is despite having the same class assigned to the team (if you can make it out in the pictures from where the arrows are pointing.
Moreover, the one shown from the Weapons tab (Frostmage) was the last used one outside of this, either in Explore or PvP, and the one shown under my Hero Avatar from the world map screen.
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First picture (Frostmage) (shown on World Map) - selected from list of all Weapons
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Second picture (Warpriest) (class assigned to team) - selected from the chosen Team
Perhaps this happens in other ‘special events’, such as Pet Rescue, and is what caused this Bug Report to be made 
.