Dawn is right. Frequent breaks are the only way to keep everything in working order "downstairs".
Regarding the loss of what you grow there are two parts:
You will lose fat when you stop the herbs (or hormones, BO, whatever...).
You will not lose actual breast tissue once you stop.
Everything you grow before you hit budding is fat, and it will most likely disappear when you stop PM. "Male fat" and "female fat" are built in diferent areas and consumed by the body when not needed. The so called "fat redistribution" is just a matter of burning the fat in the areas where your current hormones don't add to it and storing new fat in the places indicated by the new hormones. So, for example, if you take estrogen and progesterone your fat will accumulate in boobs and hip while moving away from your waist, but if you return to just having testosterone in your system then the fat will move to your belly and back away from chest and ass.
A different story happens after budding. Part of your boobs will still be made of fat, think of women losing weight and therefore losing breast volume, but whatever actual breast tissue you grew is there to stay. Keep in mind that a chubby person the volume of fat in the breast is way more than breast tissue, while in a thin person the tissue is the first thing that you'll notice. Keep in mind that breast tissue takes a long time to build. Genetic girls grow their bosom over several years and even TS girls on pharma HRT keep developing for a few years before reaching their full potential. This doesn't mean that you won't see permanent growth, just that it won't be quick. A last thing to remember is that our bodies burn fat slower than they store new one. So you will gain weight while taking any form of opposite sex hormone. Personally I like the fact that the fat goes to my hips, ass, and boobs, but many sporty and thin people are not happy about the overall softening of their body.
Regarding the loss of what you grow there are two parts:
You will lose fat when you stop the herbs (or hormones, BO, whatever...).
You will not lose actual breast tissue once you stop.
Everything you grow before you hit budding is fat, and it will most likely disappear when you stop PM. "Male fat" and "female fat" are built in diferent areas and consumed by the body when not needed. The so called "fat redistribution" is just a matter of burning the fat in the areas where your current hormones don't add to it and storing new fat in the places indicated by the new hormones. So, for example, if you take estrogen and progesterone your fat will accumulate in boobs and hip while moving away from your waist, but if you return to just having testosterone in your system then the fat will move to your belly and back away from chest and ass.
A different story happens after budding. Part of your boobs will still be made of fat, think of women losing weight and therefore losing breast volume, but whatever actual breast tissue you grew is there to stay. Keep in mind that a chubby person the volume of fat in the breast is way more than breast tissue, while in a thin person the tissue is the first thing that you'll notice. Keep in mind that breast tissue takes a long time to build. Genetic girls grow their bosom over several years and even TS girls on pharma HRT keep developing for a few years before reaching their full potential. This doesn't mean that you won't see permanent growth, just that it won't be quick. A last thing to remember is that our bodies burn fat slower than they store new one. So you will gain weight while taking any form of opposite sex hormone. Personally I like the fact that the fat goes to my hips, ass, and boobs, but many sporty and thin people are not happy about the overall softening of their body.