Subject to Bank Approval!?!?

What an awesome day!  Got an accepted offer for one of my buyers on a home he's absolutely in love with.  Great!  Go to my next appointment, where another set of buyers put in an offer on a pristine home.  They offer just ABOVE asking price.  Double Great!  BUT, get this:  When I called the listing agent to make arrangements to present the offer, the listing agent states "offers aren't being presented until Monday."  ???? ????  "Why is that?", I ask.  "Well, all offers are subject to Bank Approval."  Ummm...excuse me Mr. Listing Agent, but it does NOT state that on the listing.  "Well it must be a mistake" he says.  Mistake?  Or was that particular information deliberately excluded from the listing??? Soooo frustrating!  Vent over.