Hi Simon,

bit of log info here...
Just above the if (!aItem.recurrencInfo) {}  I've added a sdbg line that prints out the "nextRem.icalString". Also included is a sdbg statement that shows when nextOcc was null.

This is the output:
readDismissSnoozeState: nextRem.icalString = 20100903T054500Z
readDismissSnoozeState: no previous occurrence found (means nextOCC === null)

These lines must be the ones for the <CalendarItem> dumped below. That day  i have 3 reoccuring events, but only this one does start 20100903 - so i'm sure i grabbed the right one. (look all ath the bottom, there are other nextRem.icalStrings which don't match.

It really seems the very first occurence gets hit - and that hasn'T a "PreviousOccurence that can be fetched, so nextOcc is set to null.

For the timezones: i'm in GMT+2 whereas the original date is GMT-6 (Mountain Std Time)

----------------cut -----------------
           <t:CalendarItem>
              <t:ItemId Id="AAMkADc2MTUyZTFmLTRkYTgtNDQ1NC1iNmE1LWVlYTY0YzJhZmRjOQBGAAAAAABJp9XcLhx6Qrxwms0wmfqNBwAGyqTTdTxTQI0s5jQLaERCAAAE89e9AABOIkmWM7JsRrJ6RLSojS6QAItWfaCWAAA=" ChangeKey="DwAAABYAAABOIkmWM7JsRrJ6RLSojS6QAItWfcDC"/>
              <t:Subject>Inviter - OOO</t:Subject>
              <t:Body BodyType="Text">When: Occurs every Friday effective 9/3/2010 until 12/17/2010 (GMT-07:00) Mountain Time (US &amp; Canada).

Note: The GMT offset above does not reflect daylight saving time adjustments.

*~*~*~*~*~*~*~*~*~*</t:Body>
              <t:DateTimeReceived>2010-08-23T02:38:12Z</t:DateTimeReceived>
              <t:ReminderDueBy>2010-09-24T06:00:00Z</t:ReminderDueBy>
              <t:ReminderIsSet>true</t:ReminderIsSet>
              <t:ReminderMinutesBeforeStart>15</t:ReminderMinutesBeforeStart>
              <t:ExtendedProperty>
                <t:ExtendedFieldURI DistinguishedPropertySetId="Common" PropertyId="34144" PropertyType="SystemTime"/>
                <t:Value>2010-09-03T05:45:00Z</t:Value>
              </t:ExtendedProperty>
              <t:ExtendedProperty>
                <t:ExtendedFieldURI DistinguishedPropertySetId="Meeting" PropertyId="3" PropertyType="Binary"/>
                <t:Value>BAAAAIIA4AB0xbcQGoLgCAAAAACAKkfZOULLAQAAAAAAAAAAEAAAAOB4NNX9FRpApjTBPAe40CY=</t:Value>
              </t:ExtendedProperty>
              <t:UID>040000008200E00074C5B7101A82E00800000000802A47D93942CB01000000000000000010000000E07834D5FD151A40A634C13C07B8D026</t:UID>
              <t:Start>2010-09-03T06:00:00Z</t:Start>
              <t:End>2010-09-04T06:00:00Z</t:End>
              <t:IsAllDayEvent>true</t:IsAllDayEvent>
              <t:Location/>
              <t:IsCancelled>false</t:IsCancelled>
              <t:CalendarItemType>RecurringMaster</t:CalendarItemType>
              <t:MyResponseType>NoResponseReceived</t:MyResponseType>
              <t:Organizer>
                <t:Mailbox>
                  <t:Name>inviter full name</t:Name>
                  <t:EmailAddress><email address hidden></t:EmailAddress>
                  <t:RoutingType>SMTP</t:RoutingType>
                </t:Mailbox>
              </t:Organizer>
              <t:RequiredAttendees>
                <t:Attendee>
                  <t:Mailbox>
                    <t:Name>inviter full name</t:Name>
                    <t:EmailAddress><email address hidden></t:EmailAddress>
                    <t:RoutingType>SMTP</t:RoutingType>
                  </t:Mailbox>
                  <t:ResponseType>Unknown</t:ResponseType>
                </t:Attendee>
                <t:Attendee>
                  <t:Mailbox>
                    <t:Name>Group1</t:Name>
                    <t:EmailAddress><email address hidden></t:EmailAddress>
                    <t:RoutingType>SMTP</t:RoutingType>
                  </t:Mailbox>
                  <t:ResponseType>Unknown</t:ResponseType>
                </t:Attendee>
                <t:Attendee>
                  <t:Mailbox>
                    <t:Name>Group2</t:Name>
                    <t:EmailAddress><email address hidden></t:EmailAddress>
                    <t:RoutingType>SMTP</t:RoutingType>
                  </t:Mailbox>
                  <t:ResponseType>Unknown</t:ResponseType>
                </t:Attendee>
                <t:Attendee>
                  <t:Mailbox>
                    <t:Name>Group3</t:Name>
                    <t:EmailAddress><email address hidden></t:EmailAddress>
                    <t:RoutingType>SMTP</t:RoutingType>
                  </t:Mailbox>
                  <t:ResponseType>Unknown</t:ResponseType>
                </t:Attendee>
                <t:Attendee>
                  <t:Mailbox>
                    <t:Name>Group4</t:Name>
                    <t:EmailAddress><email address hidden></t:EmailAddress>
                    <t:RoutingType>SMTP</t:RoutingType>
                  </t:Mailbox>
                  <t:ResponseType>Unknown</t:ResponseType>
                </t:Attendee>
                <t:Attendee>
                  <t:Mailbox>
                    <t:Name>Person1</t:Name>
                    <t:EmailAddress><email address hidden></t:EmailAddress>
                    <t:RoutingType>SMTP</t:RoutingType>
                  </t:Mailbox>
                  <t:ResponseType>Unknown</t:ResponseType>
                </t:Attendee>
              </t:RequiredAttendees>
              <t:Recurrence>
                <t:WeeklyRecurrence>
                  <t:Interval>1</t:Interval>
                  <t:DaysOfWeek>Friday</t:DaysOfWeek>
                </t:WeeklyRecurrence>
                <t:EndDateRecurrence>
                  <t:StartDate>2010-09-03Z</t:StartDate>
                  <t:EndDate>2010-12-17Z</t:EndDate>
                </t:EndDateRecurrence>
              </t:Recurrence>
              <t:FirstOccurrence>
                <t:ItemId Id="AAMkADc2MTUyZTFmLTRkYTgtNDQ1NC1iNmE1LWVlYTY0YzJhZmRjOQFRAAiIzRkSFhnAAEYAAAAASafV3C4cekK8cJrNMJn6jQcABsqk03U8U0CNLOY0C2hEQgAABPPXvQAATiJJljOybEayekS0qI0ukACLVn2glgAAEA==" ChangeKey="DwAAABYAAABOIkmWM7JsRrJ6RLSojS6QAItWfcDC"/>
                <t:Start>2010-09-03T06:00:00Z</t:Start>
                <t:End>2010-09-04T06:00:00Z</t:End>
                <t:OriginalStart>2010-09-03T06:00:00Z</t:OriginalStart>
              </t:FirstOccurrence>
              <t:LastOccurrence>
                <t:ItemId Id="AAMkADc2MTUyZTFmLTRkYTgtNDQ1NC1iNmE1LWVlYTY0YzJhZmRjOQFRAAiIzWuUe3mAAEYAAAAASafV3C4cekK8cJrNMJn6jQcABsqk03U8U0CNLOY0C2hEQgAABPPXvQAATiJJljOybEayekS0qI0ukACLVn2glgAAEA==" ChangeKey="DwAAABYAAABOIkmWM7JsRrJ6RLSojS6QAItWfcDC"/>
                <t:Start>2010-12-17T07:00:00Z</t:Start>
                <t:End>2010-12-18T07:00:00Z</t:End>
                <t:OriginalStart>2010-12-17T07:00:00Z</t:OriginalStart>
              </t:LastOccurrence>
              <t:MeetingTimeZone TimeZoneName="Mountain Standard Time">
                <t:BaseOffset>PT420M</t:BaseOffset>
                <t:Standard TimeZoneName="Mountain Standard Time">
                  <t:Offset>PT0M</t:Offset>
                  <t:RelativeYearlyRecurrence>
                    <t:DaysOfWeek>Sunday</t:DaysOfWeek>
                    <t:DayOfWeekIndex>First</t:DayOfWeekIndex>
                    <t:Month>November</t:Month>
                  </t:RelativeYearlyRecurrence>
                  <t:Time>02:00:00</t:Time>
                </t:Standard>
                <t:Daylight TimeZoneName="Mountain Daylight Time">
                  <t:Offset>-PT60M</t:Offset>
                  <t:RelativeYearlyRecurrence>
                    <t:DaysOfWeek>Sunday</t:DaysOfWeek>
                    <t:DayOfWeekIndex>Second</t:DayOfWeekIndex>
                    <t:Month>March</t:Month>
                  </t:RelativeYearlyRecurrence>
                  <t:Time>02:00:00</t:Time>
                </t:Daylight>
              </t:MeetingTimeZone>
            </t:CalendarItem>

----------cut-------------------   
   
b87cc5ce-0929-406c-b77d-dccccff34404/HP: getItemReply

readDismissSnoozeState: nextRem.icalString = 20100903T054500Z
readDismissSnoozeState: no previous occurrence found (means nextOCC === null)
readDismissSnoozeState: nextRem.icalString = 20101001T134500Z
readDismissSnoozeState: nextRem.icalString = 20100817T151500Z