Iliyana,
The 3-day composites are offered as a convenience
but are not really part of our standard set of distributed
products.
When the Aqua-MODIS data were reprocessed,
it was decided not to regenerate 3-day composites for the
historical data. Production of 3-day products in the
"forward stream" will continue for the foreseeable future.
You can always make 3-day composites yourself from
the daily composites using
SeaDAS.
Regards,
Norman