My new SB can only get away mornings to midday, she has to be home when the kids get home.   She is talking about getting a motel check-in at 10 a.m.
What's the best way to accomplish this?  
I was thinking calling the motel direct the day before for a reservation and telling them we are traveling and expect to be in their area around 10 a.m. and could we get an early check-in with our reservation.  Thoughts and suggestions?

Noon is about the earliest I've ever been able to snag a room.   A lot depends upon if they have available rooms.

Do not ask the reservation people.  They are trained to say no to such things.

But, if you reach the front desk, you might get somewhere.

Another tactic is to reserve the room for the night before.  This is only good if you need the room for just a couple of hours because most places kick you at by noon or even 11.  You can ask for some extra check out time if needs be, but it's not a given.  Try for a day when the place is slow.  Even better is if you can go get the room the night before so you already have the key.  Put the DND sign on the door, and the next morning at 10 you and she can just go right up to the room and not lose any time at the desk which will be crowded with people checking out

You could of course call them as you mentioned and simply tell them what hours you are going to need the room and ask them what they suggest. Some places even offer half day rates, it never hurts to ask.  

When giving them a reason you can either tell them you are traveling as you planned, or you might try telling them something closer to the truth. You could tell them you are having an affair and the only time the two of you can get together is between the hours of 10-2 and ask them the best way to schedule. I suppose it would depend on whether the desk clerk appears to be a prude or not. lol

Good suggestions.

Yes, those are our exact playtimes, if this 62 y/o can keep up with a 38 y/o for that long.  My tongue never gets tired.

..Due to travel layovers and flight crew needs.

"Thank you for having stayed with us. I hope you had a good time in there. Now that I have your name, CC number, photos on the security cameras, a stained bed sheet, etc., I just need contact info for your wife or her lawyer. Or I can just look it up on my own. Of course, for a small recurring fee, I can forget that I ever saw you here."  

Admittedly, GaG did close with a "lol".

You don't mention where you are, this hourly website works well in big cities

I can actually do things like tell a desk clerk that I am only there to fuck.

Of course I am fully cognizant that others can not afford to play the game by my rules, and if the OP had said he was meeting a hooker at the motel and not an SB, I would not have given him the same advice, even jokingly. I will confess that even it I were renting a room solely to see a hooker I would probably still not be afraid to tell the desk clerk I was only there to fuck.lol

as early as 10am so I can get some rest and shower before my presentation at 3 pm that afternoon? I will be flying out later that day so you can even re-sell the room."

Have you tried HotelbyDay.com ???

Is check in the night before and request late checkout. I've noticed that it's extremely difficult to get a check in before 2:30 pm and it raises questions from the hotel.  

Thanks.  This is the way to go.