No body can tell you when you should start jumping based upon one post. It would help to see videos. That being said, everyone's definition of "when" will be different. IMHO, a rider should not be thinking about jumping before they can W/T/C with and without stirrups on their own (meaning not on a lunge line). I would never - and have never - started a student before they were fully capable of this.
I believe I started jumping ~8 months after riding. I was doing 1-2x per week lessons at the time and riding family horses in between lessons so how often you ride will depend on your ability also. A GOOD trainer will not start you jumping before you are truly ready.