Layer OutPoint doesn't update correctly when source is changed.

I am using a script to change the source of my layers and different source files have different lengths.

In the composition I am using an automatic volume fade-in fade-out with the following expression:

if (time< (this_layer.in_point  +0.5))               { (1.0 - ((time-this_layer.in_point)/.5)) * [-32.0,-32.0];  }

else if (time> (this_layer.out_point - 0.5))         { ( (time-(this_layer.out_point-.5))/.5)  * [-32.0,-32.0];  }

else { [0.0, 0.0] }

g (for a .5 second fade at the beginning and the end of the layer ). However, when I replace the footage with a different one by script, the OutPoint is not updated and therefore the expression doesn't produce the desired fade-out at the end of the layer.

When I reload the project/purge the cache, or close and reopen AE the outPoint is not changed and holds an incorrect value.

ONLY when I grab the end and extend or shorten the layer a couple of frames, the value gets updated correctly and the fade is perfect.

The inPoint, ie the Fade-In works nicely. I've tried other expressions from the forum, same problem.

Could anybody give me a pointer how I can get around this issue?

Thanks in advance.

yp