Renege on internal job?

I'm currently in a risk/compliance function at a large global bank and just accepted an offer in credit risk (CR) and put in my 2 weeks notice. I'm getting a 30% all-in raise and a promotion for this.
I also just found out that a market risk (MR) team that I applied to, but didn't interview for because of timing, wanted me bad and I would have been a perfect fit. I didn’t realize I would have been good for this group and what they were looking for, or else I would have focused my search here. This job would result in an 80% all-in raise and great opportunity at the bank. The CR role is still high profile and a good experience. Only minor concern is that what I'm doing right now is more applicable to MR than the new CR role. But I can't stand my current role and the culture there (not getting opps for development, promo, etc.)
Since I accepted the credit risk role, my application was withdrawn from the other role. My company has a policy that I need to work 1 year in the position before taking another internal job.
Should I plan to work in CR and revisit MR in a year? Or renege, stay put for a little longer and wait for MR to pan out. I have strong connections in MR. Gut is telling me to take the new job and revisit MR later, rather than piss off a lot of people by reneging.