Is it ok to transfer internally ASAP?

I recently accepted a job at another site within the company I work for (healthcare if that makes a difference, I will be switching hospitals). Per our policy I can only be kept in my current position for a month, but I can stay longer if all parties agree to do so. My old manager reached out to my new manager and asked if they could hold me for two months so as to cover vacations in July (I currently work overnights and it’s difficult to find coverage). My new manager asked if I would be ok with this. I would prefer to transfer after one month for both financial and personal reasons, would this look bad to my new manager/burn any bridges?