player manager question

if you start the player manager/mode how long you are a player/manager (so not just manager)? i read somewhere only 4 years and then your vp retires as a player. is this correct? i would like to have my vp a bit longer in my team|||I believe it is 4 years, this is to show a progression between career options. Likewise if you are a player before being a player manager you are only able to do a certain number of seasons before progressing to a different "stage".|||pfff.. thats short