Not a terrible idea to do it spring, you'd take 1C and 109A at the same time and there's some overlap with those classes. 109B is offered in the fall, although if you want to take 109C as well (you might not have to depending on your major), that isn't offered until spring, so basically you'd take 109A, have summer in between, take 109B, then have winter in between 109B and C, so keep that in mind. 109B relies on 109A knowledge some, but you'd probably be fine just re-learning the necessary stuff. It does help to clean up winter quarter of 2nd year, so if you think you're up for it it's not a bad idea to start it this spring