Here's pretty much how this goes:
Summer & fall in the admissions office:
1. Receive truckloads of apps, wade through them. Think mass movement. The only special snowflakes have high GPAs and high MCATs. Think 5000 apps per school.
2. Those who aren't above the bar for interviews get routed to the NO pile. Think 500 interview slots, 4500 in the NO pile.
3. Sometimes there's a policy to put borderline apps from current SMP enrollees in a HOLD pile pending SMP grades, if the rest of the app is strong. This is typically only going to happen at the applicant's home state public schools, or at schools where the applicant was previously waitlisted. This will typically not happen in California.
Intra-holidays in the admissions office:
1. New applications are still being reviewed from people with 3.8/35's.
2. Truckloads of new information comes in from those rejected/waitlisted/pre-interview such as letters of intent, new transcripts, new letters, and wade through them. Still mass movement.
3. Adcoms meet very few times to review new information (because holidays) and are not going to get to everything. The HOLD pile may or may not get looked at.
4. On very very rare occasions, new information changes minds and results in an interview invite.
Post-holidays in the admissions office:
1. All the interviews have already been scheduled, with room for maybe a few more to squeeze in at the end.
2. The HOLD pile gets reviewed if new info came in. On very very rare occasion, a new transcript/letter results in a HOLD pile app getting an interview.
3. By the end of January, more than enough acceptances to fill the class have been offered. After this, math models are used to predict how many acceptances need to be offered to result in filled tuition-paid seats in July/Aug. Each school anticipates that only 3/4 or 1/2 or 1/3 of the acceptances are going to stick. After May 15, as acceptances are turned down by students who get better acceptances, once a week or so people are pulled from the waitlist.
For the sake of planning:
1. If your GPA/MCAT were not good enough to get you interviews before you started your SMP, your best hope is the HOLD pile.
2. If your SMP transcript/letter is not strong in Dec/Jan, you are not getting an interview. You're going from HOLD to NO.
3. If your SMP transcript/letter is strong in Dec/Jan, you might get an interview very late in the season, and your best hope is the waitlist.
4. You very much need to be thinking about what you will do after graduating your SMP, as in jobs and student loan payments and rental leases, because your fate will not be known in May, and it may not be known in August.
More to the point, don't underestimate the GPA/MCAT of your SMP classmates who are getting accepted. People with 3.4+ and 30+ are doing SMPs.
Best of luck to you.