Should I tell my future employer about my MBA plan?

Trying to make some life decisions and thought what better way than to ask the internet.

I have 6 years of experience in sort of market risk at a top 15 bank. But I want to do investment banking. Probably lev fin. Plan is to do an MBA. I also have an offer to join a top 5 US bank also in risk. I would start in a few months, which would give me ~9 months experience in the new job before I submit MBA applications.

Questions:

1/ Should I take the offer? I think I should. Pros are a) shows I am employable and not “stuck” and b) improved brand name. Cons: the job is not investment banking. So might be tricky to explain in my MBA “story”. I think I can worry about that later.

2/ If I take the offer, should I tell my new manager my MBA plan? If I don’t, then I will have to ask my current employer to provide references, and explain why in the optional essay. And I will have to tell my new employer eventually anyway. If I do, then I’ll need to make some meaningful contributions over the next few months so that my new employer can give me a good reference. But there is also the risk that they withdraw my offer. But at least I am being honest. -- I am leaning towards this option.

what have I missed? Tear me down