Hello jessenchester, good to hear from you again.
It’s hard to make a definitive judgment without more information. I always think it is better to go with the individual who knows you and your work better, regardless of time worked together. Choose the person who can provide details and anecdotes about your strengths and who can better give an honest assessment of your abilities.
Unless the school specifically requests a current manager, then I think you have some latitude in choosing.
For your previous role, with the limited information I have, it sounds like your direct manager is a solid choice.
Best of luck,
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