Hello Andreas,
Few point to ponder upon:
If ZD and AP are in different timezones then if WLAN schedule feature would use the time set on the ZD.
Possible issue with daylight saving comes into picture.
As Keith mentioned, remote AP will inherit all configuration like channel, transmit power from ZD in a different country and this MAY create issue as when it comes to RF regulations of remote AP country. Please ensure that these settings are harmonised keeping in mind both countries.