FD you answered in 2
However if you come to that conclusion at 500ft you are going to be stuffed and best make sure you go into whatever it is, controlled and at minimum speed.
Changing your mind at this height will end in tears
a) Probably below 500ft before you see/recognise the problem
b) It is better to go through the far hedge/wall at 10 knots rather than hit the first at 60.