Qui or lequel?

Question

I understood that, when referring to people, qui should be used after a preposition, excepting only parmi and entre. Has this changed?

Céline Pickard · Accepted Answer

Bonjour Rita,
That’s right. After the prepositions ‘parmi, entre’ the relative pronoun ’lequel’ etc is used. ‘qui’ is used for living things only. 
‘Lequel, laquelle’ etc may be used for people. It is less common, and yet, it is becoming increasingly more common in ‘modern’ French.

C’est le chien qui m’a mordu = it is the dog that bit me
C’est le client avec qui je travaille = it is the customer for whom I am working
Les candidats parmi lesquels je me trouve = the candidates among whom I am
C’est le client pour lequel je travaille = it is the customer for whom I am                                                                                                                                               working

I hope this is helpful.
Bonne journée!