Awesome topic @Yogi1.
I do think that each individual has a "set point" or weight range, give or take a couple of pounds, that their body is "happiest" or where it naturally wants to be, if nutrition is fairly consistent and the person isn't eating lots of garbage or junky stuff. Depending on the individual's metabolism and genetics, it's different for everyone. Some are naturally just skinny no matter what, the "hard gainers". Personally I do not have a naturally fast metabolism, but as long as I'm training and my nutrition is consistent I can maintain easily. If I were to eat a couple of cheat meals or ease up on the nutrition, or stop training, I'd gain weight/fat for sure pretty quickly.
Finding maintenance I think is the first step in realizing the "set point" and maintaining any weight, and knowing what needs to be done from there. But to truly find your own maintenance will take some time, maybe a month, and very consistent nutrition. Keep in mind this doesn't mean dieting per say, but consistency in eating the same macros/calories every day, or sticking to whatever the plan is. As I'm currently in a gaining phase, finding my maintenance was crucial to make sure I didn't go overboard with my surplus. So I created a nutrition plan based on a rough guesstimation calorically, got my macros ironed out and just stuck with that. I still weigh myself every day to see rough fluctuations, but I go always with the lowest weight of the week as anything else on top of that is just water/food volume. After 4 weeks of having the same low weight, or within half a pound, I knew what my maintenance calories and macros were. Then to hold that weight, just stick to your maintenance plan. So yes, I do think it's best to find maintenance and maintain there for a while to be sure that when you start cutting calories and adding cardio, you know for sure you'll be losing fat.
EDIT: I realize I never really directly answered this question. I think it takes about a month to know for sure you're at maintenance, so when you start your cut, you want to be sure you know what maintenance is. After that, you start your cut and begin to lose weight/fat. Depending on your timeline, you can wait longer before making adjustments. I think at least 10-14 days at a weight before making further adjustments is necessary to make sure you're not rushing (more info on that below.)
Now this is an interesting subject, because once you find your maintenance, it might be possible to maintain at a different weight. For example I'm at 162 right now, but am cutting for the next few weeks to try to lose some fat before a trip I have. I've cut carbs a little bit and added in a couple of weekly HIIT sessions. I'm hoping to be in the 157ish range by the time I leave, so it'll be interesting to see once I get to that weight if I go back to my current maintenance plan, will I remain at 157, or creep back up to 162? I am guessing I'll stay closer to 157, but if I start gaining again, I'll know my "set point" is closer to 160-162, so I may have to find a "new maintenance" for the 157 area.
Now in terms of getting your body to "accept" a new weight, I do think it's very possible to do, but is dependent on a few factors and is totally different for everyone. I think the first time you really try to cut and get very lean, the body puts up more of a fight then it will subsequently. After my shows when I started gaining again I had a much easier time staying lean, and at my current weight of 162 I'm definitely leaner than I was last time I was 162 7 or 8 months ago. @BrickHead, @The_Mighty_Stu and I have talked about the fact that once you do it the first time, it's easier to get there again and the body naturally can stay a little bit leaner. Although if you go haywire on nutrition then you'll just go right back to where you started.
So for your cut, I'd recommend first finding your maintenance at whatever your current weight is by creating a nutrition plan, stick with it for a month and see what happens. If you start gaining weight, you know you need to pull back, if you start losing then you know you can add another 100-200 calories. Once you have your maintenance, start with a 10% deficit and a little bit of cardio, don't do too much to soon because your body will really start putting up a fight then (I learned that the hard way!)
Cutting is a tricky beast, it can take a few weeks before the body even starts responding. So you may find your maintenance, start your cut only to find the first couple weeks nothing is "happening", then you question if that was really your maintenance. Although, it IS working, your body is just getting used to it and results may not be visible yet on the scale or in the mirror. It took me 3 weeks when I started my cut to lose the first couple pounds before things started moving along at a more consistent rate. Once you start losing, just keep with what you're doing, and if eventually things stall completely, like maybe it's been 10-14 days without a new low and you don't see any results in your progress pics, THEN you make another adjustment, cut cals a little more, a little more cardio. It'll be easier to find and maintain a new "set point" with this approach, rather than rapidly making adjustments, either with nutrition or cardio.
In terms of maintaining a new set point, again I do think it's easier to do once you're leaner, and to get to that new set point will again just take consistent nutrition. Your "maintenance" at a lower weight may indeed be lower than maintenance at a higher weight. Personally I can certainly eat a LOT more now and maintain weight than what I used to be able to do, although I don't think that would be the case if I didn't diet down for the show.