With the chance to win yet more ranking points before the year's end, she has her sights set firmly on qualifying for next year's first gram-slam junior tournament - January's Australian Open in Melbourne. This year she lost her last qualifying match - a defeat that cost her a place in the main junior girls' draw.
"Playing in a grand-slam event is intense," Katherine says. "All the opponents that you meet are top players in their countries and the atmosphere can be breathlessly nervous."
Katherine, who is ranked 158th in the world, has stopped playing in local Hong Kong tournaments so she can concentrate on playing in international tournaments. She is confident of claiming the points she needs to enter the world's top 100 so she can enter the qualifying tournament once again.
After playing in this year's Australian Open qualifying tournament she decided to quit her Form Four studies at Diocesan Girls' School.
"I'd missed too many school days over the past few past years travelling to so many places abroad," Katherine says.
"It was really tough for me to catch up with the class and all the homework. I planned to study at an online school, but Mum didn't allow me to do so before. But this time she's let me decide myself."
Katherine is now a Year 11 student at Laurel Springs School, a California-based online private school. She always completes both her lessons - and sends in her homework on time while travelling to tournaments. "Hopefully I can get a good grade point average and can enrol in universities in the United States," she says. "I hope to receive high-quality training at university and - depending on my fitness after graduation - I may play as a professional, if possible."
Katherine started playing mini tennis when she was four, and had regular coaching from the age of six. She won the first Hong Kong Tennis Association tournament she entered, when she was only eight.
Although she joined the national junior squad in 2002, she left after two years to train on her own. "It didn't fit me, so I decided to train by myself," says Katherine, who has played in four Junior Federation Cup team tournaments.
Katherine turned her back on local tournaments at 14 to focus on playing International Tennis Federation junior tournaments around the world - accompanied by her mother. "I used to watch her matches," says Elki Ip.
"Now I rarely watch; she's got too conservative. When she's held set points or match points, instead of attacking she's been defensive; I don't want to get angry."
Katherine, ever the competitor, disagrees. "This is my strategy; I like to play long rallies and am always confident of forcing rivals into errors.
"I'll try to be more aggressive at the right times in the future."
If she secures a place at next year's junior Australian Open we will know her strategy has worked.