KöMaL 2013 B4507

The area of a regular heptagon is 4095 units. $A$ and $B$ are two consecutive vertices, and $K$ is the centre of the heptagon. $P$ is a point lying on the circumscribed circle of triangle ABK in the interior of the heptagon. Given that $\frac{AP-PB}{AB}=\frac{2}{3}$, what may be the area of triangle ABP ?