I suspect that your bottle is still within the useable shelf life.
All the Scott bottles do indeed go through annual testing as well as hydrostatic retesting. Scott composite tanks have a "shelf life maximum of 15 years". This is from the date on the bottle:
This bottle can no longer be re-certified for use and can no longer be refilled.
Scott has since produced some carbon fiber composite bottles with an extended service life of 30 years.
Just wanted everyone to be careful. There are lots and lots of these old surplussed composite bottles still around. Know if it can be refilled before you buy one.
Cut the bottom off and make a lamp or bell out of the expired bottles.
BTW, this bottle and the other couple I have come from my department . I have been there long enough that I was here when they went into service and helped replace all of them.