Obviously, not an exact science but how do you guys and ladies like your appointments?  I travel a lot for business so 2-3 weeks in advance works best for me.  Have had a couple of conflicting results planning, basically short notice was not enough, 3 weeks and she canceled a few days before.  
Even local I usually need 2-3 weeks in advance to plan a good time

good week or less, as it's just enough time but not too far off IMO. But that's only because I'm not a fan of waiting lol. Sometimes with the longer wait, there can be too many factors that can get in the way.  

For a time, I was booking months in advance with gents who knew they were travelling in for business and wanted to book then. It was a lil too stressful for me as I just never knew what 'could've' happened by the time our month would roll around. I'm a day by day kinda girl as much as I can be. So I stopped doing that and simply tell them to let me know 2 weeks before they're planning to come to town and we'd be good to go.  

1 or 2 weeks is good on the average. On occasion 3 weeks, but again, who likes to wait that long. This world is a rather impulsive world IMO, and acting on impulse can sometimes bring about the best results if at all possible.  

We want what we want when we want it lol. I think that goes for both sides of the coin here

Good luck to you and I hope noone cancels on you again. That's not fun for anyone here.  

xx kisses

Because of business I don't have many free slots on my calendar, so I like to line up something well in advance.  I sometimes schedule something on 1-2 days notice, and sometimes I book farther out.  In fact, my last 3 sessions were booked 4-5 weeks out... each one had some special circumstances.

I just like to get a day set so I can do the things in advance that need to be done at my leisure.  When it comes to cancellations or something else that's gone wrong, it wouldn't have mattered if I booked two weeks or two days in advance.

An example of the advance stuff. I like to bring a bottle of decent wine or whatever other beverage the provider mentions on her site. The county where I live only became wet a year before I moved here, and that was due to pressure from restaurants, especially those close to the interstate. But most folks don't drink, or don't drink much, so there's nothing in the way of a good store for wine. The nearest is in the next city over, which is a 90 mile round trip for me. I'd rather do it the weekend before than add that to my trip on the day I go out of state.

I generally try to make my dates about a week in advance.  I don't travel, so it might be harder if you are not sure what your traveling days will be.  Do not understand why you are having troubles with scheduling 2-3 weeks ahead of time for traveling.  Since I do not know where you are, it's hard to know why you are having troubles with scheduling.

Swim

...I set things up 3 or 4 days to a week out.

If I'm traveling, I'll schedule about a week out. Reconfirm a few days before. If its a traveling lady, I'll schedule as soon as I see the ad, (sometimes more than a month) usually they won't get back to me if they do at all or they waiting until far to close to the date to contact me. I think they may be trying to gauge if an area has enough business to actually schedule going there. Locally, I normally do a few days in advance up to a week. I never feel too bad if they need to cancel or if I do. (rarely) Shit happens.  

Advanced notice is always appreciated  
The further in advance the better