In my house I have a not very new upvc window (fitted by the previous
owners) and in cold weather there is a bad draft from the bottom left
corner of the bottom half, which opens upwards from a central position
(it is like a sash window in appearance, though not in operation). I
can in fact see out through this gap.Its about 2-3mm wide.

Is it possible to adjust/move the hinges so that it will close this
gap?

I can see that the panel that opens is not quite central at the
bottom, seems to be less of a problem nearer the top.

Window looks like this:

xxxxxxxxxxxxx
x x
x x top panel is fixed
x x
x x
xxxxxxxxxxxxx - hinges are here
x x
x x
x x bottom panel lifts from bottom up, outwards
away from room
x x
xxxxxxxxxxxxx

Any help or advice is appreciated.
Thanks