Just want to put in my datapoint. I flew JFK-FRA-SIN on Suites a couple weeks ago. Arrival time in SIN was extremely early. Too early for me to check in my hostel. I went to the lounge and inquired about Private Room access. One of the girl lead me to the check in desk to the Private Room. I told the woman there I was on an early flight and waiting for a friend(not really) to arrive. She had no problem letting me inside. I stayed all the way until 1pm. Had breakfast and lunch there. Note I was on an arrival flight, did not have a connecting or departing ticket.