How did the GMAT go? That will play a role in terms of the overall 'tiers' of schools you may want to aim for.
I'm not sure if you mentioned if you are applying this year or next? Your experience is very limited and if possible I'd recommend waiting a year... b-schools really prefer more experience so that you are bringing a lot to classroom discussions etc. The average is closer to 5 years of experience. And within that, they really appreciate seeing progression, results, accomplishments, leadership skills, teamwork skills, communication skills, and times you went above and beyond what was expected of you. It's tough for me to assess based on what you've provided here, but I'm not sure how much of any of those you've been able to experience or demonstrate within the 23 months?? The start-up (?) experience you describe is one area of interest and a plus, but otherwise to have a chance at reputable b-schools you really need some great experiences you can discuss to help you stand out. It also sounds like you are making a big career switch which isn't necessarily a problem generally but on top of a potentially weaker profile, it could be tough.
I am not sure I'd even say BC is safe, but maybe Purdue. Your stretch schools AT THIS POINT are going to be very difficult to get into. I want to encourage you to reach for your dreams but also need to be realistic! With more time and key experiences on top of a strong GMAT, your chances would increase.
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