Completing Wayfarer's Reverie after August 30th

Is it possible? Thing is, I have started playing recently and already have access to all continents but not to all areas required to complete the Reverie (still gonna take a while too...). can i collect the quests rewards later then the 30th?

Not possible, it's an event and once the event ends the quest will vanish...

They count as festival quests, so they remove the NPCs after the event is over; you therefore won't be able to turn in the quests even if you do them. Unless they make an exception and leave them a week or two after, maybe only allow players to turn in the quest, you're out of luck.