Help with Power Auras!

[Valorus]

Hi, I'd like to know how could I setup up a buff (doesn't matter which) to appear only UNTIL a certain duration (let's say first 40 seconds)...But so far I've only found the opposite. By using the option under "Timer" tab, "Hide Aura and Timer until Time Above". So is there actually a way to do what I wanna do with Power Auras? Or not? Hope there is...Cause I don't wanna be forced to switch over to weak auras and spend hours after hours of searching for codes to do the things I wanna do with my buffs / auras / CDs etc. etc. Somehow Weak Auras doesn't seem so easy to use and configure.

[Resike]

Version:4.27.4; buffname:Battle Shout; duration:40; icon:Ability_Warrior_BattleShout