Schedules hill climbing on a sierra (5)
I believe the answer is:
rotas
'schedules' is the definition.
The answer and definition can be both related to communication as well as being plural nouns.
Perhaps there's an association between them I don't understand?
'hill climbing on a sierra' is the wordplay.
'hill' becomes 'tor' (tor is a kind of hill).
'climbing' says the letters should be written in reverse (in a down clue, letters climb up).
'on' means one lot of letters go next to another.
'sierra' becomes 'S' (phonetic alphabet: alpha, bravo, charlie etc.).
'tor' written backwards gives 'rot'.
'rot'+'a'+'s'='ROTAS'
Can you help me to learn more?
(Other definitions for rotas that I've seen before include "Duty lists" , "Rolls" , "Rosters" , "Cycles of duty" , "they tell us when to work" .)