The SCWPM lists two date varieties for the 10-rufiyaa from Maldives (Pick 19): 1998 and 2006. As it turns out, there are actually two varieties dated 1998. The difference is that the first variety has the printer imprint of DE LA RUE at bottom center on back, whereas the second variety is without the imprint, as is the 2006 note. The transition from with to without imprint takes place between serial number prefixes C and D.
Courtesy of Bill Stubkjaer.