>>I don't think so. First, I am using a military time, 00:00 to 23:59. So, noon is 12:00 and it is just a number.

Nope, that's not military time. That's normal 24 hour time. The military time has no colon and treats the time as numbers, where "hundred" means hours. It's a code.

>>I am just specifying From and To time (e.g. From 00:00 to 23:59 or from 01:30 to 13:20 and so on). Then I am simply checking if the current time is within the specified From and To times. I would say, that the only problem the program would have is if the current time is 23:59:59 and a fraction of a second. But I don't care about this case.
>
>To clarify --- the problems that I mentioned could arise if you selected 24:00:00 notation for midnight. By selecting the 00:00:00 notation you avoided them.

While 24:00:00 may be required in some cases - those cases are for display only. The one case I know is on railway, where a train arriving at midnight arrives at 24:00, while the train leaving at the same time leaves at 0:00. The display only value should be stored (or at least passed) as 23:59:59.999 and the problem would be solved. Or at least hidden.