W56P MULTIPLE LINES

Hi.
I am a new voip system user. I currently have W52P phone as part of the system. However I have 2 voip lines. W52P can only handle one incoming line.
I see W56P says 5 lines. Are we talking about 5 incoming lines or is this something else?
Thanks
Keith
PS Timeline is urgent. If someone can respond asap that would be awesome!