Hello Welshorp, welcome to social Slimmers
There is nothing wrong with you joining SW at your current weight. My SW book states that the lowest acceptable personal weight target for your height is 9st 13lb. That's if you want to lose some weight. They don't advise you to join if you want to lose less than 7lbs.
Your current weight would put you right in the middle of the Healthy BMI range, which may be why they advise you don't join??
And no, they don't advise you to just eat whatever again once a person reaches their target weight. They advise slight changes in your daily plan (increasing your dairy and fibre intake) but SW is mostly a lifestyle change rather than diet so it's changing habits for a lifetime rather than cutting things out completely like some plans (in my opinion at least!)
Have you tried working out more? If you aren't already that is. Maybe focusing more on your torso than anything else? I obviously don't know what you do now, but increasing your exercise will obviously help change the body fat into muscle.
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