We can collect 7200 coins (600 every 8 hours) + 150 from the start = 7350 in total. Collectionstimes are explained below.
To claim Fencing we will need 8520 coins. But on the way we can get 40 puzzle moves and 120 orbs for Bastion.
Collectiontimes:
Open the eventwindow. In the upper right corner besides the event name you see the timer .
This timer started with ....days,23hours,59minutes (on phone it doesn`t show minutes).
It will count down to 00d 00h 00m.
You have three timewindows of 8 hours every day to collect 600 eventpoints (coins).
Ignore the days , just check hours and minutes of the timer.
These are the timewindos to collect the coins:
23h59m-16h00m.
15h59m-08h00m.
07h-59m-00h00m
So you have 8 hours to collect the full amount of points. After that time a new timewindow will start and you start collection for the next 600 points. So it is possible to get ready with collecting 600 points ten minutes before the window ends and then after 10 minutes collect again 600 points because the next timewindow started. Just bring the time the timer shows in relation to the time your clock shows and you find the times for your timezone. I hope this is helpful.