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"I will not be in office till Monday".

In British English, what does the above statement mean?

a) I will be in office on Monday.

b) I will not be in office on Monday also.
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It means that you will be in the office on Monday, but you will not be in the office on any day before Monday.

It should be "I will not be in the office till Monday". (Except in the unlikely event that by "in office" you mean "appointed/elected to a position".)
Comments  
In any English, it means A.
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 Mr Wordy's reply was promoted to an answer.

I will be in office on monday

I will be in the office on Monday.

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