It is still an issue with the latest build (revision #264624/27310), despite the numerous reports in the last few months and it is not only a visual issue:
PVPBuildingDamageTimeSundayStart=0000 doesn’t accept anything but the default value.
If you change it via the in-game panel, it goes back to 0000 as soon as back out and the setting is not saved in ServerSettings.ini.
If you change it in the ServerSettings.ini, the value is saved but ignored.
Most of the PvP private servers had to resort to disabling raid time on Sunday completely.