I'm quite in a situation where I don't know how to react properly. I'm a provider from another company in a mission at my client's office and I've been here for a year and a half now.
Today my boss got back from 1-month vacation and during his leave I was asked to replace him temporarly as it is not my main job but as a Junior I thought it would be a good experience.
Also today the boss of my boss came in my room to tell me I'll do the job my boss used to do for my team.
I quite like this position of managing but this brings so much more responsability as I'm only a junior developper for a provider, I would gladly stay in this position if it was for a pay raise but it would require me to ask for my company's manager for a pay raise because the mission changed so they would notify the change to my client.
I'm not sure the client would keep me if the payment would increase.
Is it a proper way to ask for more money to my company without endangering this possible promotion ?