There are actually a few options for this. For adjusting the volume line(with all its automation intact), zoom out so the entire song fits on the EDIT window. Grab the volume line AFTER the last break point and drag up/down.
Option 2-Drew's Trim tool
Option 3-open the last plugin on that track and adjust its output up/down
Option 4-insert a TRIM plugin after the current last insert and adjust the TRIM plugin output.
Option 5- if you have no dynamic plugins on the track, you could just Clip Gain it up/down.
Option 6-(you don't need any more options
)
The cool thing about digital is; there's 4 ways to do everything. The bad thing about digital is; there's 4 ways ......