The question n is, do you fear being called out? Are there people in your everyday life who would care enough to notice?
If not, I would suggest try to stay at your current weight for a while, see if you feel self-conscious after you get used to it. Then proceed in whatever way is right for you.

Statistically, there's going to be one.
With rising obesity rates, some U.S. (or maybe Canadian or European) city will become more than 2/3rds obese, and it'll be pointed out as "the fattest city".
Not to count out the rest of the world, but that's where it'll be pointed out.
My bet is on the South, or maybe somewhere in Wisconsin.

Seems to me you want something like a many pocketed shirt you could maybe put sand in? Adding weight around the waistline, breast, underarms, hell, even arms if it was a special shirt. The sand (or whatever somewhat liquid object) would spread naturally downwards.
Of course, this would have to be a real dedicated custom job to be good.

I put on most of mine when I was pretty young. I grew a foot and put on probably 75 pounds in a year and a half?
So yeah, it's definitely about the speed of your growth.

While mine would probably be pretty impressive in a push-up bra, there's a pretty thick ring of fat going around under my arms and into some really meaty back fat.

At 430 pounds, I was about 59 inches. Now (405) I'm probably about 57?

Happened to me recently too.

Damn. I am big. And tall.

Mine are D cups.
And my back rolls are Bs!

I hadn't noticed this in men's, but I guess that means I'm really closer to 58 or 60 inches around.
What bothers me is how fatter shirts vary so wildly. Sometimes I can fit into a 4XL (rarer now though, I'll admit,) but sometimes I can't button a 7XL.