4.9 is nothing to be worried about.  One of my IDs also has 4.9 for speed of postage and I almost always post the moment the payment is made.  Well, if it is made at night I post first thing next morning, but as I am only up the road from our PO I am usually able to post immediately.  The only thing I can think of is that couple of people bought BIN Friday night and I posted Monday.  I could have posted Saturday morning at our agency, but if I do, the parcel will sit there till Monday night anyway.  :_|