If there are days between posted cities, those are days OFF.
You (any man really) would be extremely resentful if your workplace reached out to you on your evenings, weekends, and literally every holiday, because everyone needs a mental break from work. I may tweet on days off, because tweeting is fun. My tweets can tell you if I'm working, but the act of tweeting in and of itself is not working. I'm not "clocking in" because I tweet.
Checking a few dozen hotels for fine print to make reservations, verifying screening, booking, and taking schedule change requests on a day off isn't a day "off". Tweeting doesn't require a time investment and hours of concentrated attention. Again, these things are not the same.
Also I'm not "back in" a city when another city ends. I'm in a city when I post I'm in a city.
If I'm in a city for a few days then there are a few days blank then another city a few days after the blank space, please don't wait until the blank space or the arrival date in the second city to book. The blank space, again, is my very limited time off (I work every waking hour of every day of the year until sheer exhaustion drives me to take off a brief few days, so while you're unwrapping Christmas gifts or eating Thanksgiving dinner with the family, I'm working. I do almost nothing but work, and the body and mind can endure that to a point - that point is pretty far for me, but it does eventually exist). Honestly no one's life should be all work, but while I normally just play the hand I was dealt and grind it out endlessly with no "life" to speak of, just born to wake and work then sleep, eventually my body forces me to take a small break. If I've driven myself to my absolute limit and then taken off a few brief days and even those few brief days end up consumed with work interruptions, hopefully you empathize with the problem (empathizing means picturing yourself experiencing what I'm describing, admittedly a difficult exercise for people who don't view providers as human).
A second city after a blank space also needs to be booked during the first city's tour because I can't be wondering *if* I'll have any clients in the next city or get stuck with a last minute hotel cancellation fee all through my days off (again, a day off is supposed to be a mental break, not a mental strain where I spend the whole day distracted and worrying).
Stop waiting until day of arrival to book if you want me to actually arrive. I have to cancel cities before the 24-48 hour industry-wide hotel cancellation window or before I have days off (aka days that don't show at all on my calendar). I don't have a trust fund. I'm not an "elite" escort who "won't get out of bed for less than 1K" (a real tweet I saw recently). My financial margin for error is razor thin, so I cannot outlay hundreds to over a thousand in funds to maybe work (but I have to spend all that first to find out). Once I cancel your city it's very unlikely I can get back a new reservation that's anywhere near the (already barely affordable) rate I'd initially researched for literal hours to find. Hotels can't be re-booked same day unless one has deep enough pockets to pay any amount. I will book a city initially only if I can afford it. If client flakiness makes me have to cancel I can no longer afford to re-book at inevitably newer, higher rates.
Peak times exist in this industry just like any other business (clients are fond of comparing SW to other businesses until it comes time to something being required of clients like understanding rush times or showing ID or paying cancellation fees - just like other businesses). Please don't look at my ad for a week or two but then wait until Friday at 11 AM to request Friday at noon. Instead of bombarding me with a deluge of requests on Monday morning consider I've done this for many years and already know you're with your wife on the weekend and you can still surreptitiously pre-book with a play email and burner account by just slipping out to the bathroom because no, I'm not going to slip up and let her know (to what end would I do this).
Bottom line is if you can't pre-book I can't visit. I don't ask for deposits. I don't ask for a 5 point screening, only 1 thing. If you can't meet the very reasonable ask of screen and pre-book I can't be there, there being anywhere.