K.K.
I agree with Suz that it's surprising that so many people are saying just to suck it up and CIO, given your clearly stated beliefs. I also thought it was hilarious the woman who sent you your own post as a warning against what could happen if you AP too much....!
Look, your son is not getting enough sleep and you know that. The situation is already untenable, and it simply will explode when the new baby comes. I am kind of amused that we're all taking it as some kind of actual timetable, that the baby is coming in two weeks; unless you're having a scheduled cesarean, I imagine this means you're at about 38 weeks now and that means any day now, or not for up to a month. Which is to say, a lot of this is already out of your immediate control.
If you just let it go, the likelihood is that you will find yourself doing some kind of CIO simply because logistics will dictate that: you only have so many arms, and if you're coping with more than one child, then sometimes someone is going to cry. That's reality. So, if you really don't want to do CIO and you really do want to try and get a handle on this before the baby comes (assuming you don't deliver in the next few days, which is totally possible), then you are going to have to do some serious work on your own, you are going to have to take control and you are going to have to parent your kid.
It's not time for tough love on him, it's time for tough love on you, hon.
This means: the phone ringing after 6pm must go. Take whatever nesting instincts and energy you have going on right now and get yourself to Best Buy NOW and find a solution. You have no choice: you MUST arrange for the phone to stop ringing after 6pm. Whether that means it blinks red when someone is calling in, or it forwards to a vibrating cell phone, or whatever. Find a solution, take one of the many suggestions you've been given, and get it done.
This also means: you figure out and write down a schedule that works for you. Now. Sit down, and write it out. At 13 mos with A. 8am wake time, you can fudge his bedtime as late as 8pm, but that's it. So you backtrack from there: in bed by 7:30, stories/songs/snuggle at 7, bath/PJs/teeth at 6:30, dinner at 5:30/5:45, afternoon nap over by 3pm, etc. etc.... Write out a schedule and stick to it. Get some discipline and make your son's sleep and your son's schedule your absolute priority.
If I were you, feeling as you do about CIO and with #2 as imminent as he is, I would focus on these two things. I would get the sleeping arrangements manageable (meaning that there aren't obvious and avoidable things like the telephone interfering with sleep) and I would get my son on a schedule and get his sleep cycles under control. For now, I would not worry about ~how~ he goes to sleep, but more ~when~ he goes to sleep, and how much he sleeps. He NEEDS his sleep, and you need him to sleep if you want to maintain your sanity during the coming months. And, once he's on a regular, realistic schedule that is actually in tune with his body's needs, then you will be in a better position to address the rocking vs. crying debate. Once he knows what is coming, he will be better able to understand what you're asking of him. It actually sounds like the transition will not be too bad, once he's on a schedule. (You may want to check out Elizabeth Pantley's book, The No-Cry Sleep Solution, but only if you have time after you've addressed your primary issues.)
I'm sorry to sound so dire and so forceful, but you've been putting out posts and asking for help and trying to get your head around this stuff for weeks now, and the deal is, you must cope. You must take this situation and actually make it tenable. You must ensure that your oldest son is getting the sleep he needs so that he can have the internal resources to handle the complete world-change that's about to hit him. You can't keep blaming AP for what's going on. You can't keep saying you know what's wrong but can't do anything about it. You can't keep hitting a wall and asking people to tell you what to do and then hitting that same wall again because you're being ruled by inertia.
Or rather, you ~can~ do these things, but if you just keep running in circles like this, nothing is going to change. And you are in for a very rude awakening, I'm afraid.
I say this with compassion, not judgment. I hope you can hear that. I wish you the best. I have been in similar shoes to yours, and your road is going to be rough, but I know that if you cope, if you find the resources to actually address your issues, you're going to come out of this like a champ.
good luck,
K.