Firstly am sending you both huge {{{hugs}}}
I too have a 4 month old and she is a torture where napping is concerned. She is my second though and my first wasn't great at napping until 5.5 months and then it all fell into place so there is hope!! So at the minute I am rolling with it.
I am bfing and we haven't quite made it to a 4 hour EASY yet. Its more like 3.5. A lot of BF babies don't transition to a 4 hour EASY for a while yet. Are they managing 4 hours between the feeds ok.
One thing I learned from my first is to put a limit on how long you extend a nap for...I ssh-patted for 10-20 minutes and if she didn't go back to sleep in that time I got her up and got on with my day. My sanity would not have taken any more extending than that.
With a short napper it is totally ok for your EASY to be EASASE if you know what i mean? SO keep your feed times regular and work your A and naps around it.
So if you feed 8 then 12, you may find your morning goes like this:
8am Feed
9.30am Nap
10am Wake up (not able to extend)
10-11.15 A time (shortened A time because of short nap)
11.15 Nap (45 minutes)
12 Feed
Make sense?
The only thing that has worked is staying with her on her room, so every time she stirs or jolt or open her eyes I just put my hand on her shoulder, or turn her to a side (she is a side napper) or put the paci on....sometimes it works and I manage to extend naps until 1h. But I've being doing that long time and she still not capable of resettle.
My LO used to wake at the 45 minute mark without fail. I used to go in at the 30-35 minute mark and replace her paci and ssh her bck over and she would then make it through the sleep cycle and continue napping. I did have to do that for weeks and then she started making it through on her own and taking longer naps herself. But in my eyes I preferred that quick intervention than a short nap.
There is a lot going on at 4 months. Huge growth spurt (probably accounts for more NWs), BF babies often become much more efficent feeders so length of feeds decrease, often become distractable feeders and lots of developmental stuff going on so its no wonder their napping can be up the left!
I am crossing my finger in a few more weeks things even themselves out.
What A time are your LOs managing at the minute?