Got an atrocious registration time, how can I stay on track to transfer in time?

Bit of tldr background: left Berkeley after one semester (this past fall semester), completed 14 units with a 3.4 GPA, plan to TAG to UCSB. Due to calgrant hold limits, I must finish my time at CC by the end of spring 2020 and acquire 30 units before fall 2018.

As the title states, I compared my registration time to my peers and I am nearly a week after them, and I am at one of the largest CCs in California infamous for the lack of classes due to the crowding (Mt SAC). How do I go about this? Mt SAC is the only CC I’m able to attend due to relying on my dad for transportation since he works in Walnut. I’m taking 4 units in the winter intersession right now, but I’m a bit paranoid of barely being able to get 1 or 2 classes during spring. The counselors are all booked for weeks right now and I also need prerequisite clearance. This is all extremely frustrating and stressing. Anyone ever had to deal with a similar situation?

I have some units of AP credit, but unfortunately UCSB TAG requirement only allows for a maximum of 10.7 semester units to be used. Would this still help significantly?

Clarification and a typo *must acquire 30 units before fall 2019, because UCSB’s TAG requires this.

I would register for the classes (hopefully you can waitlist if you can’t get in), then show up really early on first day and get the prof to sign you up before others. There will always be no-shows.

Have you thought about taking online classes at other CCs?

^^excellent suggestion. Santa Monica College has a large online offerings.

https://isiscc.smc.edu/pls/apex/f?p=123:1::HIDE:NO::P1_STATUS,P1_SUBJECTS,P1_LOCATION,P1_INSTRUCTOR,P1_BEGINWK,P1_MEETDAYS,P1_STARTIME:,