When writing TSbackground the next version of OSDBackground my collegue Johan Schrewelius spent a lot of time analyzing how time is set during OSD in Configuration Manager in WinPE. The whole purpose being to display the correct time, time zone and time elapsed during OSD. We thought it would be a good idea to post it here as more could benefit from it.
It seems that it uses different variables with different deviations depending on how the WinPE/OSD was launched. The table below shows how time is set in WinPE depending on how was launched and which action TSBackground will take to correct the time.
The tests were done using ADK 1809,1903 and Configuration Manager 1810,1902
I hope this is useful!