Awesome job on that! I updated the letters on all my vehicles. However, I think you need some kind of reminder note on the site to tell people of this update. I didn't see the change until I went to edit my vehicle text and then spotted it.
Also, I looked over the help on SMS article, to see if it works as I suggested, but found it was not updated, so you may want to update that article too so others know of your enhancements
Oh and it looks like I made a tiny mistake in my description, I omitted [distance]. I'm sure you got it right though...
[Vehicle letter optional] [cost] [volume] [p optional] [notes optional]?
But it should be:
[Vehicle letter optional] [distance] [cost] [volume] [p optional] [notes optional]
That is what you implemented right? So:
c 200 3.00 10.0 p half-full
would mean, partially filled vehicle c, with odo reading of 200 mi (or if that vehicle is set for trip odo, then at 200 miles used), $3.00 a gallon (or liter, etc), 10.0 gal (or liters), comment "half-full".
And the fact that p for partial fill can't have a space, makes sense and answers an unasked question I had about how to parse "p" from partial vs "p" from comments. You can tell the difference because the comments has a space before it. Sorry, my geek side getting out