Just an encouragement -- in case you don't already do so -- to keep observing and enjoying sunsets through the twilight phase. This can be hard sometimes because dinner prep may be calling or the urge to concentrate on fishing may be compelling, but twilight colors can be memorable. This is true, too, for twilight before sunrise, but you have to pry yourself out of the sack to see it. Here are 2 pictures taken 20 minutes apart that illustrate my point, and the last is not even as late as we waited for the light to finally fade.
And don't forget to add your sunrise/sunset pictures to the September photo contest. There are some lovely photos there already.