Hummm. Sorry, I again question the wording. The episode scheduled to air on August 26th is the 12th of the season, which is typically the half-way point of the season, not the final episode. You might want to check out TV Rage's episode guide for PLL.
OTOH, that episode guide shows ABCF (and thus M3, which airs episodes in day-and-date sync with ABCF) airing new episodes from now right into the beginning of October...which would be very unusual. For the previous 4 years, ABCF has aired new episodes only until the end of August and then taken a break. In season 1, the break was right until the new year; in seasons 2, 3 and 4 the break was only until Halloween, when they aired a Halloween-themed episode followed by a break until the new year. I strongly suspect they will follow the same pattern this year...particularly since Holly Marie Combs is currently on some kind of a well-tweeted "road trip" with her kids and BFF Shannen Doherty, and not on the PLL set.
So, given the airing pattern of the previous seasons and the fact that the 26th is the last Tuesday of August, if you change the phrase "final episode" to "mid-season finale" (or even "summer finale", which I believe is the phrase that ABCF uses), I'll be happy to leave you alone :-)