Beijing car owners will have to change their no-car day this month, the local transport authority announced on Monday.
The ban, which took effect on Oct 11, has caused much confusion to motorists who feel it is too complicated.
Starting from Monday, some cars previously banned on that day will now be allowed on the roads. They will not be allowed on Tuesdays. Cars banned on other days of the week will also move back a day.
The ban has been imposed to ease Beijing's traffic jams and cut down on pollution.
Divided into five groups, currently cars with license plates ending with "1" or a "6" are banned on Mondays, those with "2" or "7" are banned on Tuesdays, and so on. Weekends are exempt.
But vehicle owners are finding the rule so confusing to the extent Beijing Youth Daily runs a front-page notice each day to remind drivers.
"Changing the days, I fear, will lead to confusion. People are likely to forget when they can and cannot drive their vehicles," Robert Miller, a Canadian media consultant, said.
However, there are some who admit the rule is confusing but are quite willing to accept it if it reduces traffic and pollution.
Philip Tinari, an American art consultant, said: " I think it (the ban) has been effective. I am willing to trade off a day for less traffic on the roads."
Mao Baohua, a Beijing Jiaotong University professor, supported the government's move to ease traffic congestion and reduce pollution.
"In Beijing, for every 24 hours, one hour is wasted in numerous traffic jams," he said. "I don't oppose car ownership, but I suggest efficient car use. And how we do it? The government must improve public transport and do it quickly," Mao said.