[squiggleblaz]

Midnight never refers to 11.59pm, which is one minute before midnight. I can say that for certain.

Normally I would take "midnight on Friday" as an instant to mean 2400, since if you're somewhere at 1am on Saturday morning you wouldn't consider it a problem to say "we were out partying on Friday night", but if you were there at 11pm on Friday night you would consider it a problem to say "we were out partying on Saturday night.

However in the particular case of something beginning, I would normally take take it to mean "the very start of Friday according to legal time".

Likewise, in the particular case of something ending, I would normally take it to mean "the very end of Friday according to legal time".