Clan Points Transfer

Recently I have seen players coming into the clan already having clan points.
What are the reasons for players to carry clan points?

This is what I have heard xp:

-If it is your first clan, you recieve the clan points gathered before hand since the player began playing CF. (Heard this recently but from a Smilie Face ^^ so im sceptical)

-Lt and leaders carry their points to their next clan if they leave their original clan. (dont realy believe the LTs one though)

-It is a glitch (i probably would prefer a mod or something to actualy clearify this one xp)

-If you leave your previous clan and join a new one within a certain time period you retain your points. (how long can you carry the cp?)


I appreciate all comments ^^ thank you and GG o.o