[General] We will have ten days time/ten day's time and indefinite article "a".

[Aamir Tariq]

Before we get promoted to the next grade; we will have ten days time.
Before we get promoted to the next grade; we will have ten day's time.

Should we use indefinite article "a"?

Before we get promoted to the next grade; we will have a ten days time.
Before we get promoted to the next grade; we will have a ten day's time.

Can we also use the following with "of"?

Before we get promoted to the next grade; we will have ten days of time.

Regards
Aamir the Global Citizen

 

[Rover_KE]

For a start, all the semicolons should be commas.

 

[Aamir Tariq]

None of them is natural. I am not sure exactly what you mean. Are you going to be promoted ten days from now?

I mean you have vacations after you have your final exams, then the result is announced and then you get promoted to the next grade.

So I am talking about that gap, that time period when your final exams are over and you have a few days to enjoy yourself before you start taking classes at the next grade.

 

[tedmc]

We will have a ten-day break after our exams before starting classes for the next grade.

 

[jutfrank]

I think this is actually a natural way of speaking, but certainly rather uncommon these days, and certainly unusual in this case.

The correct form should be: "we will have ten days' time."

Because ten days is plural, you don't need an indefinite article and the apostrophe cannot go before the plural -s. It's a possessive form so the apostrophe goes after the -s. (The meaning is similar to your suggestion: "ten days of time".)

I would say the use is to emphasise the duration of a period. It's most commonly used with in to refer to a future point, as in:

I'll still be waiting in two years' time!