When does the Weekly Heroic Strike reset

You can play the weekly strike once per character and receive rewards on each character - so if you have 3 characters, you can get up to 27 coins per week, if you can do it on the hardest difficulty with each.

Yes it will count for Ikora part III, since you are still doing the weekly heroic strike, there is no limitation if you have already done it this week.

Just remember you won't get any loot for it, it will only count for the mission.

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