Clock Reset After reboot workaround
Warning: It works on my phone but I cannot guarantee that it will work on yours. I have now tested it under a different timezone while travelling and it works. You do this at your own risk and nobody will pay your ticket if you miss your train or plane in the morning! 
Thanks to @Roboe for pointing in the right direction!
Requirements
- FP2 with rooted FP OpenOS
- Install Clock_Offset_Fix_2.2.apk from this location: http://forum.xda-developers.com/showthread.php?t=2580974
- Install the “Kernel Adiutor” app from GooglePlay https://play.google.com/store/apps/details?id=com.grarak.kerneladiutor&hl=en_GB
There is an older version of Kernel Adiutor on F-Droid, but that did not work for me.
OK, lets go for it:
- Make sure your FP2 shows the proper time.
- Open the “Clock Offset Fix” app and click on "Install offset and initscript"
Important: This fix does not update the offset-file regularly so you will have to update it by clicking on “Install Offset” whenever you have “cold started” your phone (removed the battery). - Open “Kernel Adiutor” and go to the “init.d” section (listed under "tools)
- Enable init.d support (slider to the right and pink)
- click on the + sign to add a new script
- call the script rtcfix, your horses name or whatever you like, but no special characters.
- Simply add the following line to the script (leave the #!/system/bin/sh as it is):
/data/local/userinit.sh - Save and you are cooked !
- You can check the script by tapping on the entry in the init.d section. It should show the current time as result.
Test your setup:
- WiFi off
- Mobile Data Off
- Aeroplane Mode On or remove SIM
- Wrap your phone in tin foil if you want to be really really sure it does not get the time from outside.
- Shutdown phone
- Start phone again
- Things going well Kernel Adiutor will set the time after approx. 10 seconds (the default delay) plus boot time.
