BA check in opened at 7.30pm on Tuesday so 4 hours. We like the Qantas lounge, the staff are very friendly and proactive. There is a massive difference in the offering between the BA and QF flights. While QF passengers are in the lounge 3 or 4 times an hour the staff come around with little hot and cold treats plus the offering on the buffet is more substantial. Flying to SYD last month my wife was in the lavatory when a round of nice fries came around. One of the bar staff said he'd get her some more and disappeared, our flight was called and he ran out with a plate of fries, he went to the bar and made a paper cone to put them in, outstanding service. Once the last QF flight goes the treats diasappear and the buffet offering diminishes, the drinks stay the same.
It's very clear BA pay QF less hence the lounge goes downhill. Fortunately on Tuesday one of the QF flights was delayed so we were better looked after!