Hello!
I don't know the exact stats to get into the program, but this website
https://www.barry.edu/biomedical-sciences/admissions/ should answer all of that
From my experience, I have plenty of friends (including myself) who didn't have stellar undergrad GPAs and still got into the program if that gives you some insight.
As for how tough the 1 year program is, your ability to handle the BMS course load really depends on what kind of GPA you maintained while taking like 15 credits a semester. At Barry since you're getting a Masters to show improvement from undergrad it's really important to get a 4.0 or very close to it. Most students only take 9 to 12 credits a semester which is 2 to 3 classes. That may not seem like a lot, but when it comes to graduate school trust me it's a whole different ballgame. I did the 18 month track and it really worked for me. Something to consider - some schools won't even look at you until you have a year of graduate work under your belt so it might be more worth it for you to do the 18 month track to make sure you get all A's rather than pack everything together and not do as well in your classes.
They offer fall, spring and summer classes - and you can begin the program during any of those semesters.
Fall classes start in late August usually and the exact deadlines for applying can be found here:
https://www.barry.edu/biomedical-sciences/admissions/application-process.html
Hope this helps!