https://theboard.byu.edu/questions/64413/
Melyngoch deferred her Stafford loans while on her mission and I don't recall that being an issue when she went to put her papers in. (Maybe the fact that she was in grad school instead of undergrad made a difference?) I think she did have to pay off a private loan beforehand, since those can't be deferred.
#64413 - Student loans and missions
Moderator: Marduk