The latest increase, which is the second adjustment in flight frequency in a short term, indicates a trend for both parties to expand flight operations.
150 domestic and foreign airlines plan to arrange 16,680 flights per week, reaching 68 foreign countries.
The airline has so far resumed 59 international routes after COVID-19.
Passenger numbers rose by 480% year-on-year to 1.5 million in the months with the load factor up by 11.2 percentage points to 83.7%.
The partnership allowed Qantas and China Eastern to coordinate passenger and cargo movement between Australia and China.
The post soon garnered the attention of netizens, with more than 25,000 likes as of Tuesday.
Singapore's Jetstar Asia and Indonesia’s TransNusa have also announced new routes to Mainland China.
It remains to be seen how this decision by HK Express will impact the city's strength as an aviation hub, especially with the growing threat posed by Shenzhen airport.