What did you seek in the discovery request?
And, unless the citing officer amends the citation to something more appropriate (such as VC 21453(a)) you should prevail on a VC 22450 citation for a stoplight.
Seems a rather grievous error for the officer to have made to confuse VC 22450 and VC 21453, but if so, it should be an easy one for you to prevail upon.

