Question: When did the Australian become part of the Grand Slam?
The Open Era started in 1968, Oz became the 4th the following year.
What next for Bianca: Beijing.
Her record is truly remarkable, the only player to beat her outright,in 2019, is Julia Goerges. Up to Indian Wells she played 8 qualifying matches, she got laid low by the heat and humidity of Melbourne, she withdrew in the 3rd round. With so many matches her shoulder gave out.
Beijing is a mandatory tournament like Indian Wells and the Roger's Cup, just below the Grand Slam. Since she's now in the top 10, she doesn't necessarily have to compete but she will. She'll want to get as close to No. 1 to give herself the best possible draw for the Australian Open. After that comes the Season ending Tournament of Champions in Singapore. Only the top 32 compete there, if she wins that she's No. 1.