Why?

Since stones are being accumulated (and we've already gone through this -- SEVERAL TIMES):

The "maintenance" is 289 hours.

Meaning that, even if you had zero stones at the time of the closure:

If you have no abyssites to shorten the time (I believe Celerity), you would have 14-15 stones.

1 such abyssite gets it to 18.

2 such abyssites, and you now have 24.

And all 3?? Try 36!

Methinks Abyssea (and especially some of the more popular NM's) is going to be quite crowded in a little less than 18 hours.