Senior Year S&T Regional Boutique Internship - Then What?

I'm a recent grad with a Sales and Trading internship lined up.

My first two summers in college, I worked at a Fortune 500 company (in marketing), but the company itself was in financial services. Additionally, I spent a quarter at a BB in PWM and have done an internship with a small private equity firm. I'm at a top 20 university with a good but not great GPA.

I spent my junior year summer working at a start up. I was always torn between start-ups and finance (mainly S&T, although I looked into IB even though I'm more of an S&T person for sure).

I'm trying to figure out what I go after this S&T internship. This company isn't particularly known for their conversation from intern to full time. Even if I did get a FT offer, what would I do for a year waiting for when the internship began?

Anyone know of is banks ever recruit for S&T roles outside of the traditional internship to FT cycle? Additionally, if I did FT recruitment for BB, would I be able to start in January for instance?