We are getting Charter phone added Wednesday. The faq says:
Number Of Phone Lines

Charter will install up to two separate phone lines and a distinctive
ring for residential customers. If you need more than two separate
phone lines please contact Charter Business at 1-888-692-8635.
http://www.myaccount.charter.com/cus...Ofphoneli nes

I really don't need two different phone numbers, but since the second
line is free, I was considering how I may use it.

I currently have 2 cordless phones with 3 handsets each. One of the
base phones is right where the router (and UPS) is located at the
house. I am considering putting a single jack for that phone on the
main phone number and then letting the rest of the jacks in the house
be supplied by the second phone number.

I don't know how the phone equipment connects to the phone system.
What would be nice is if the phone guy would just install a jack that
has two ports. One for each phone number.

I could then plug the base into one jack and that gives the 3 most
important phones the main phone number.

For the second line, I have a base block next to the equipment. I
could just take a 6' phone cord and jump between the second line and
the new phone jack line 2. This would make the entire house then be
on the second phone line back feed through the room jack.

Would this work?

If it turned out that I would really want the other base (and the rest
of the house) on the same number, I could just change the jumper and
put all the phones on the main number.