The question you asked is about when the second surgery for retinal detachment should take place, which implies that the first surgery for retinal detachment failed, necessitating a second surgery. Due to the proliferation of the retina, which generally peaks around two to three weeks, it is recommended that if the first surgery fails, the second surgery should be conducted about 10-14 days after the first surgery, which is about half a month later. This timing can help reduce the failure rate of the surgery and avoid the peak proliferation period of the retina.