I seriously could not disagree more with the "range of time" meaning "you can show up any time you want". If that were the case, I, too, would want "blank" as the check in time because I will not be held hostage in my own home for 8 - 10 hours a day "in case" the guest shows up whenever. There is a basic lack of mutual respect that goes along with failing to communicate about travel plans or making sure you are not completely inconveniencing the host who is graciously letting out their room to you at a fraction of what the local hotels offer. Hopefully I make that crystal clear in my communication beforehand and in my house rules. When a guest wants to give us a "range of time" this is the message we send them:
"We have busy lives. Since it's our home, we would like to commit to an arrival time with you. We both have commitments and jobs that often force us to be away from the house. There is no full-time staff, it's just us, so we need to make sure one of us is available to greet you, let you in, and show you around. There is no remote key or keybox and we'd hate to leave you stranded on the porch wanting to check in while we're off running errands. We hope you understand. We'd be happy to put you down for a xxpm check in if that works for you. Then we can set about planning our day around your arrival. "
There is absolutely no reason I should be "surprised" at my own front door with the arrival of a guest I am not expecting at that time any more than a guest should be surprised to wait for an hour because I'm off running an errand. Airbnb is built on the ideals of mutual trust and respect. If you were arriving at your friend's house, you'd tell her exactly when you were coming to her home, why should any host expect less than that same courtesy?
My guess is that Airbnb sided with the guest because of the email exchange that happened between the two of you afterwards but we'll never really know.
We have several very expensive concert tickets coming up in the next few weeks. There is no way to note on individual days when we have a conflict to the normal check in "range". We are not able to post that on Friday the 18th check in needs to happen before 7pm or after 11pm because we are not going to be home. We do not have a co-host to come by and check in guests for us when these occassions arise (nor do we want to pay for one) - they doen't even offer it here in Durham. So what's the solution.... we can never go out ever again - we're booked more than 90% of a given month?
This is most definitely an opportunity for Airbnb to reconsider the Host Voice suggestion that they make a guest pick a check in time at the time of booking.