... Must be uploaded by 11:59 p.m. (GMT) on April 12, 2016.
What does "by" mean in this context? Does that mean "before"? So the deadline is on April 12 at 11.59 p.m. GMT?
And 11:59 p.m. = 23:59 (24h), right?
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Sign up to join this community... Must be uploaded by 11:59 p.m. (GMT) on April 12, 2016.
What does "by" mean in this context? Does that mean "before"? So the deadline is on April 12 at 11.59 p.m. GMT?
And 11:59 p.m. = 23:59 (24h), right?
Even to native English speakers, "by" is ambiguously either inclusive, or not inclusive of the date/time being mentioned. For example, if you say "have it on my desk by Friday", some English speakers will interpret that as including Friday, and some (like me) will not. That's one reason why people often try to make it more specific, as they have done here, so that the ambiguity is not as important.
Judging by the very specific time, I'd interpret this as an attempt to make clear that the data must be uploaded before April 13 2016 starts. 11:59pm is 23:59 on a 24 hour clock.
By a date means before but including that date. If you do not want to include that date, then use before instead. So "By Feb. 2" means before Feb 3. If you do not want to include Feb. 2, then use "Before Feb. 2".
Personally, when I hear or read 'by' used in a similar context (in the question), my interpretation is that the person who delivered the message means:
"Do this, because by that specified time, I am expecting that it is done." (Of course the person won't tell you whether or not that task would be checked by that time)
In this case, uploading, make it sure that if there's a lag in the system, the file must be 'visible' and 'accessible' when the person checks it during the specified time.
Regarding your interpretation on 11:59 PM - it is correct. The deadline is on April 12, at 23:59:XX.
'By' means any time but before the specified time.
So, if the deadline is April 12 11:59 pm (i.e. 2349 hr), 'by' would be any time before it.
If you upload it exactly at 2349 hr, it'll be 'at'.
must be uploaded at 11:59 p.m. (GMT) on April 12, 2016.
This means at dot 11:59 pm.