Be Here Now. This script uses Cyber Engine Tweaks to sync the in-game time to the real-world time (given your system time is correct). So 24 hours = 24 hours. In addition you can now also pick a custom time while maintaining a 24-hour cycle.

Was looking for this but couldn't find it so far, so wrote it myself and thought I might as well share it. 

Like most time tweaks I'm not sure what kind of influence this has on the flow of the game and missions but things seem to work. Many people have reported most missions work with a few rare exceptions. 

Install:

Unzip in  ..\Cyberpunk 2077\bin\x64\plugins\cyber_engine_tweaks\mods\ 
(the init.lua should be in \Cyberpunk 2077\bin\x64\plugins\cyber_engine_tweaks\mods\realtime)

Use:

Script will run automatically.
A message in the console will confirm that the script is loaded. Your time in the game should now be synced to your system time, a day will last 24 hours.

New in version 0.3:

Set a custom time while maintaining a 24 day period.
To enable the 'custom time' GUI you need to set a Hotkey using the Cyber Engine Tweaks overlay. More info here:
https://wiki.cybermods.net/cyber-engine-tweaks/console/usage

If you use the custom time GUI make sure you also open de Cyber Engine Tweaks overlay so you have a mouse cursor.

Disable:

press the hotkey you set to call the GUI and press the "stop script" button
OR rename the init.lua in ..\cyber_engine_tweaks\mods\realtime to anything else, e.g. _init.lua

Uninstall:

Simply delete the realtime dir in ..\cyber_engine_tweaks\mods\