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It is likely discretionary on the part of the individual lendor.
Do you have a potential lendor in mind? If so, I would give them a call and request preliminary advise from them on exactly how they interpret or apply any discretionary criteria on FHA loans.
I think you should be OK. I got an FHA loan while in rehab. I was honest about it. You may have to write a letter stating that you are paying your student loans on-time. Talk to your mortgage broker about it.