Haven't Heard Back From Student Finance

Earlier this month, I've mailed my Confirmation of Customer Details form to Student Finance but I haven't got a response from them yet.

Does it usually take this long for them to acknowledge my form?

Hi Lalalalalalamember,

Sorry for the delay in this reply.

Have you had a response yet?

Thank you,

John.

No I haven't.

Are they supposed to let me know that they've received it?

When I first sent my Customer Confirmation form in 2013 they never responded back (although I didn't have to repay because I was getting jobseeker's allowance), and in 2014 when they asked me to provide my updated details (after HMRC had told them that the details they had about me didn't match) they sent me a response telling me my details were received.