Talk:FGO 2016 Summer Event/@comment-118.200.186.3-20160822051521/@comment-27247829-20160822052149

The event as a whole ends on August 31, and Part 1 is listed as ending on that date also. This implies, even if you didn't finish part I by now, you can still finish it and proceeds to part 2 as soon as you can unlock it.

In short, yes, you still can.