A company I have a small investment in has been struggling to get the most recent version of their software shipped. A few weeks ago I ran into the CEO who grabbed me and said "we are almost ready to go live." I looked at him and said "when is the release." His answer was "Friday."
I gave him a Bronx cheer and said "when on Friday?" He looked at me like I was an alien. I clarified – do you mean "12:01am on Friday, 4:59pm on Friday, or 11:59pm on Friday." I then clarified some more: "and I mean in Mountain time." We agreed that 11:59pm on Friday was a good time (which they missed, but they got it out a few days later.)
At my first company (Feld Technologies), our client base got to the point where we were often doing multiple releases of different software on a weekly basis (we were a custom software company but used a very traditional software engineering approach to our projects.) For a long time, we used dates to mark releases (e.g. "Friday.") After way too many 11:59pm releases (where our clients definitely were not sticking around the office to wait for us) and missed Fedex deadlines (this was back when you had to Fedex the disks to the clients in another state because modems were too slow to transmit the files), we learned that a release has both a date and a time. We also learned that the external release is – at the minimum – date + 1 of the "internal release" especially on systems with live data. We also learned that the only appropriate days of the week for a release are Tuesday, Wednesday, or Thursday. I’ll let you guess as to why this is.
As I work with new startups and first time entrepreneurs, I see people learning this lesson over and over again. I think it’s just going to be part of the endless education of new software entrepreneurs that you never really learn until you are in the real world.