According to the manual, if the H is lower than 33', it ascends to 33' prior to RTH. If higher, it stays at altitute. Looked at the new Win GUI (hopefully an OSX version soon) and noticed no ability to change the 33'. If filming something at less than 33' in a wooded area where the trees are >33', it would be nice to be able to change this paramenter in the GUI. Any intentions in giving us this flexibility?