Singular and plural (The publication[s] department)

Hi,
1/The difference btw “The publications department” and “The publication department” is……………
2/ The difference btw “The appointment board” and “The appointments board” is……………
Alandro

Hi,

Your answers are?

Alan

No, I don’t know. Normally, when we have NOUN+NOUN, the first noun is usually in singular. However,sometimes I see “the appointment board”, “the publication department”, some times I see “the appointments board”, “the publications department”. I don’t know how they differ from on meaning and on grammatical structure.
Alandro