2 lines on family plan now, if we add a third, can we remove one of the other two?

Question

My husband and I have a 2 line family share plan with standard phones (sharing 700 mins/month w/ unlimited text).  I'm eligible for an upgrade now (primary line), and he has to wait until June.  Our contracts both expire in October.  We both want to upgrade to a plan that includes data, and probably both get the droid 2, which are buy one get one free right now.  However, they won't allow us to upgrade his phone yet, and so I can't use the bogo offer. 
It seems there's also a "smartphones talk free" promotion right now too.  So to add a third line with a smartphone we'd only pay for the data plan, not the $9.99 for the extra line.  So I guess I'm looking for the loophole :-)  Would we only be paying for our two data packages, and for one of the extra lines?
If we add a third line, can we then take advantage of the bogo offer with my early upgrade and the new line?  Ideally my husband would just use the new line, and let his old phone sit until October, and then we'd go back to only having 2 lines on our plan.  Would we be able to cancel his current line in October, or would adding the 3rd line extend the contracts of all three lines on our plan?
Also could we transfer his current "line 2" number to the new "line 3" phone?

Answer 1

spottedcatfish wrote:
Here's the catch.  The line that is using the "Smartphones Talk Free" promo has to have a data package attached to it, which means that you would wind up in this situation:
Your Number (Line 1) - Calling Plan + Data Package
His Number (Line 2) - $9.99 + Data Package
New Number (Line 3) - $0 + Data package (as long as the data package is kept on the line)
You'd have to have 3 data packages, one to keep the promo, and then one on the lines with the smartphones active.  Contracts and promotions are tied to the phone number, so you can't switch the number or contract end date between lines.  If your husband wants to keep his number, the best thing to do will be to wait until he is eligible for an upgrade.
If there is not a smartphone on line 2, but just a standard phone as was stated by the OP, you do not have to have a data plan on this line. To qualify for the smartphones talk free promotion, you do not have to have a data plan on all lines, just the lines you sign up with the offer for, i.e. just the primary line that is upgrading to the smartphone and the additional line that you are adding so that you can take advantage of the offer.
If you do want to take advantage of the smartphone talk free offer, though, you will have to leave the smartphone on the line you sign up with. If you move the phone to your 2nd line, I believe that the discount will be stopped.