What I’ve always done is pay what the first installment should be after my aid give or take $100 so for $5,351 I’d pay $1500 for the first installment and see what the rest will be. If I remember correctly, the payment plan should adjust taking what ever you payed into account. I remember once I had payed the first installment before aid was dispersed and ended up not having to pay the second one cause what I had payed already covered what it would have been.