You like to sync appointments after a specific date?
Since the current version, you can use ExMixedFolders to match elements that are older than a date you have selected (today - x days). For appointments, the time of the appointment is compared and for all other objects the "LastMofdification" time is used for the comparison.
There is also another function called "Synchronize only future changes", which only addresses changes that will take place in the future. This function is almost completely replaced by the above one. You can only use the function together with "Reset synchronization".