Population has mushroomed from 300,000 to 680,000 in 30 years, while proportion of senior citizens expected to reach 14 per cent by 2024.
Community
Some 75,000 pupils at kindergartens, primary and secondary schools stand to benefit.
Tourism officials blitz Chinese social media while also dangling promotional hotel and air ticket coupons.
Passengers can change their booking to a date before the end of June next year, however there are four holiday blackout periods.
Students need to return to their place of residence before next Tuesday, and take NAT if they travelled beyond Zhuhai or Zhongshan after 6 August.
Potential risk of importing Covid-19 outweighs potential benefits, even though families are desperate for help and workers are more than willing to come.
Doubling the schedule indicates that there is increasing demand for travel between the two cities.
New housing will accommodate residents of rundown walk-ups built in the 1970s.
But pupils and staff – and family living with them – who travelled beyond Zhongshan and Zhuhai after 6 August must take NAT.