Overnight repair?

Not sure if bug or feature... I usually play at night and early on next day. All my vehicles are Tier 1 or 2 so short repair times... It is common for me to login in the game in the morning and have a couple vehicles still repairing...after 8h or so. They will mostly repair if i play a few minutes... Does the repair time counts only time while LOGGED IN? I am using PS4...it will shutdown after a while. But i thought this was irrelevant. And i also thought repair time would keep counting even with game shut down.