Does anyone have any experience with the 3 hour long slots for these classes? They say they are combined sections, but are they any different as opposed to the regular 1 hour long lectures?
I can't really understand the profs in my current time slots and i'm wondering if it's worth it to switch.

Combined section just means that your 1ZB3 class will have 1AA3 students and your 1ZC3 class will have 1B03 students since they're all the same courses. You would just learn in one night what other students would learn in a week. Though one caveat is that since it's a night class and it's 3 hours long you may have trouble focusing.

I'm assuming you have Chinese postdocs for both? I found that in these two courses in particular, since they follow the textbook quite closely you really don't need to understand what they're saying. Just copy down whatever they write on the board. It's the process and the examples that they cover that's important. If anything is unclear about what you wrote down you can refer back to the textbook and fill in the gaps yourself. These two courses are pretty calculation heavy, 1ZB being more involved and 1ZC being more trivial (such as row reduction, inverses, small definition chasing proofs). If you still have questions you can still go to the other profs office hours since there's 4 profs for engineering alone plus 2 others for non-engineering so you've got about 6 profs to help you (including your own). I've noticed that one good thing about having a prof whose English skills are not that great is that people stop asking stupid questions which allows the material to flow uninterrupted. When a prof speaks proper English, students tend to ask some weird shit that's totally unrelated to the material or should be asked during office hours, or they ask really simple stuff that can be answered on your own if you just do the practice problems in the textbook.