This is quite common. Some guys are quite busy and when their dick is telling them they must have a shag they do the craziest things. Plus they are trying to hide what they are doing from their work or whatever. Some are genuine, most are not. They'll have you jumping through hoops and then still not come. Goes with the territory and you have to learn to manage it and work around it.

He actually sounds quite genuine and a nice guy and does not sound like a TW. He made an enquiry late last night on the off chance for lunchtime today and did not receive a response. He therefore amended his schedule accordingly, maybe something came up or he found someone else. You responded at 09:45am to say he could have the appointment and he responded within 45mins to say it was no longer required. Even if he was free, by you not responding until 09:45am he wouldn't have known whether he was coming or going, and depending on where he was coming from, less than 2 hours notice from the time he saw your message to the time of the appointment is really not a realistic notice period as it could take him that long just to get to you. I doubt that you could/would just drop everything to attend somewhere just off the strength of what was nothing more than an enquiry so that's probably all it was.

Yes, I get that. But in his last message he did apologise for it being so last minute and he would contact me next time with more time to spare. If they can justify a last minute request, then I should be able to justify a last minute response. I think I check my email with sufficient frequency, so any last minute requests are usually met with an understanding of a last minute response. He didn't sound annoyed in his emails, more embarrassed that he had for whatever reason changed his plans