Promotions delight some at first with envy occasionally admitted (10)

'promotions' is the definition.
The answer and definition can be both acts as well as being plural nouns.
Maybe you can see a link between them that I don't see?

'delight some at first with envy occasionally admitted' is the wordplay.
'delight' becomes 'elation' (elation is delight or glee).
'at first' suggests taking the first letters.
'with' means one lot of letters go next to another.
'occasionally' indicates alternate letters (letters taken at regular intervals or occasions).
'admitted' means one lot of letters goes inside another (inserted letters are admitted in).
The first letter of 'some' is 's'.
The alternating letters of 'envy' are 'ev'.
'elation'+'s'='elations'
'elations' going around 'ev' is 'ELEVATIONS'.

Can you help me to learn more?