Sometimes it is necessary to widen the Prior Days in each relationship to capture the first occurence of a Recurring Calendar Item.
Sometimes it is necessary so the item is included to sync to relationships for changes to old recurring items. Sometimes they are not being tagged by our separate recurring item sync routine. This was often caused by making the appointment in older versions of Outlook.
The best thing to do for OLD recurring items is to stop the recurrence of the older items, and then make a new one for that recurrence pattern going forward. This way it does not have to replicate so far in the past to get the master recurring appointment.
Currently, in order to connect and sync old recurring items, we had to set the prior days to replicating 2 years in the past for every relationship.
This is not optimal from a replication standpoint, because a bunch of OLD items are replicating, and most are not changing, and this strategy will work if they don’t want to edit the old active recurring meeting items, (there are probably just a few) then edit and stop the old ones on the last recurrence and then recreate new ones for the same meeting going forward. If this was done, we could change the relationships to have a smaller date timespan and thus replicate faster. Then they could make the exceptions to the new ones and they would all replicate within the shorter timeframe of the relationship.
Again, if they did go ahead and edit those items, stop it the last occurrence and then create new ones moving forward, we could shorten the days in the past we are replicating for every relationship and their sync times would be much shorter.
The current strategy, to lengthen the prior days of sync and widen the timespan, will work as is, and if you want to adopt this strategy in the future, or over time, the settings could be changed then, with perhaps only a year in the past.
If you don't use the edit and end and then recreate in the future strategy, In less than two years, when these item changes are not being replicated to everyone, you may have items which again probably don't replicate. At least you will know how to manage this. Again to be clear, if over time you edit the old ones and recreate them in the nearer future, without missing a scheduled recurrence, we can avoid any issues moving forward and then be able to edit the relationships for a smaller timeframe.
Hope this helps!