Hi I don't have exact answer but can relate experience of a family friend. They had their LPR status GC. they were travelling a lot back and forth between home country and US and I knew they weren't sure if they wanted to maintain their LPR. At certain point an immigration officer warned them that if they leave US again (within next x number of months) they'd lose their GC. They did leave between that time period and on return, Their GC was taken and they were issued 10 year multiple entry visitor visa.