I create an event to repeat on the 1st day of the month every two months starting 1st April.
Not sure what it means but an exported .vcf contains
RRULE:MD2 1 #0
When synced to a phone using aCalandar the event on the phone occurs annually on the 1st April.
The aCalander debug info for the event contains
rrule = FREQ=MONTHLY;INTERVAL=2;BYMONTH=4;BYMONTHDAY=1
and I understand BYMONTH=4 means the event only occurs in April and it should not be there.
I think (but can't be sure) this used to work. Don't know if myphoneexplorer changed or if aCalander handling of contradictory rrule elements changed.