The Changeable Hawk-Eagle (Nisaetus cirrhatus limnaeetus) has both a dark and pale morph (and an intermediate one as well). So it doesn't actually change from one morph to another, but exists in different plumages. Perhaps Variable Hawk-Eagle would be a better term (or Three-Morph Hawk-Eagle).
I will be doing a trip report, but I have to finish sorting and labelling my pictures. Then the slow, laborious process of writing up each day adventures.
Will be uploading some pics from Sungai Seria and the Billion Barrel Monument area in the next couple of days, and next week some pics from Taman Jubli Perak.