ASKWB

As far as I know the term ‘Sui generis’ means a transitional phase of service – neither permanent nor temporary (quasipermanent). It’s an old concept.
I think friends from state govt. services may clarify it in a better way!

Thanks to Living Fossil and Humanity First.
In this connection, I like to ask further, What is substantive and officiating appointment? Sorry, if I am asking too much.

Burton’s Legal Thesaurus gives us to understand that “sui generis” is a Latin word and it means “in its own category, in its own group, of its own character, of its own class, of its own classification, of its own denomination, of its own desiggation (The choosing and naming of someone to be the holder of a position), of its own genre, of its own kind, of its own nature, of its own type, of its own variety, peculiar, special, the only one of its kind and unique. These types of terms are the flowery and twisted words and are generally used by the administrators in the own interest keeping full power in its hands. I believe I am clear.