Scars for deffo a year, and not normal lotion, as even factor 50 isn’t designed for the high uv intensity, boobs are supposed to be a year too, but three months is enough time to allow the skin to settle down from being stretched.
I went on holiday three months after both BA’s, and had bikinis on (which we all know don’t cover all your boobs) and factor 50 under my scar away sheets to protect my incisions, and I haven’t tanned blotchy on them (obv real sun is different to uv lights, but it’s the same factor with tanning) xx