Best time to apply for MBA ?

I have worked for a year at a BB bank (think Wells Fargo, HSBC, TD Bank). I have been working as an analyst and really love the company and overall culture. However, I’ve noticed that my org doesn’t really offer any kind of MBA/higher education sponsorship or assistance. It is a dream of mine to got to a T10 MBA and am not sure what to do… my current role and company doesn’t require a masters for upward mobility but feel like I might have to make a lateral move to a more competitive company so I can get into an upper echelon MBA program. I graduated college early and have a ton of internship experience but don’t think it’s competitive enough for grad school.. thoughts?