Chp Ticket Near Long Beach, Court Date On Catalina Island???

Location: Los Angeles

Title says it all... I was pulled over near Long Beach for speeding by CHP. The whole traffic stop had an odd vibe to it. Officer was very aggressive. He forced me to sign his iPad saying that I will take care of the citations. He never explained what I was being cited for, so I asked "what am I signing for?" He responded "if you don't sign I can drag you down to the courthouse right now." So I signed, and only then did he give me the citation. I then realize I had been cited for speeding, AND for driving without a registration.

Here's the problem. My registration is not expired. I have this year and last year's registration in my car, and I gave him the old expired one on accident. My plate clearly has 2027 tabs, and if he had told me my registration was expired, I would have just produced the other document for him.

To top it all off, my court date is on Catalina Island, a courthouse that is open one Friday a month... Has anyone else had to go to Catalina for a court data? Normally, I'd assume it's a clerical error. But with the whole vibe of the traffic stop, I wonder if this is an intentional way to ensure I don't show up to contest the citation.

I almost got out of my car and walked back to his cruiser to ask about the Catalina court date and show him the non-expired registration. But he was already testy enough and I honestly was worried he'd throw me in the back of his cruiser for approaching his vehicle.

Am I able to fight this traffic stop on the procedural grounds that the officer didn't even explain I was being cited for, and I therefore had no chance to prove my innocence? I know that cops have a hard job and have generally had good interactions with police. I was not confrontational with this guy, but it felt like he was out to get me from the start.