Two birthdays - one real, one official - are good enough for Her Majesty and now it seems for all pupils about to join primary 1 classes in Glasgow next August.
As a means of bypassing recent placing request legislation that the Scottish Executive admits is flawed, the city is to set a "commencement date" for P1 entry at February 28 next year, although pupils will in fact have started school in August.
Confused? Many are.
The city has now deemed August 20 as a "starting date" for P1 entry, while the "commencement date" is almost seven months later in 2002.
The anomaly is a technical device to ensure all parents of children eligible for entry can make a request. Unfortunately, last summer's education Act changed the legislation but forgot to change the wording of "school age", which is defined as five. This overlooks the reality that in first year many children are aged four-and-a-half.
As the law stands, parents of such children are excluded from making a request. This was not the intention when the Executive drew up legislative amendments, a point accepted in a clarification letter to authorities in mi-January.
The city's cunning switch will ensure all children are five or over by the "commencement date".
Paul Romano, city council solicitor, last week told councillors: "We can actually have two different ways of calculating the age of any child. There is the real age from the date of birth and a fictional age depending on where the authority fixes the appropriate commencement date."
Mr Romano accepted it was an unsatisfactory compromise that might not stand up in a sheriff court. "The alternative is to ignore this and do nothing but that would not be a reasonable approach for the largest authority in Scotland to take."
Parents would be prevented from making placing requests if they did nothing, a situation that could lead to greater legal problems. "I'm not guaranteeing success. There is a limit to what I can do within the limits of the Act and there are dangers in any of the choices," Mr Romano said.
The Executive pledged to bring in amending legislation at the earliest opportunity and has asked authorities to take a reasonable approach. It accepts the courts could take a different view.