Hi there! Just adding my two cents'...we had to start cutting back on one of DS's naps when it got to be too much A time + naps to fit into the day. This is what we're currently doing (and he does ~4h A times):
Awake 7
A: 4h15
S: 11:15-12:45 (1.5h)
A: 4h (sometimes a little less to make this an UT nap)
S: (4:30) 4:45-5:15 (30 minutes)
A: 3h
Bedtime between 8-8:15
The 2-1 transition doesn't happen abruptly, so what will happen is one of two things:
1) Short AM nap/long PM nap (with a reduced A time in the middle). This is good if your LO has started refusing to sleep after a certain time of the day.
2) Long AM nap/short PM nap (with a reduced A time at the end of the day).
So, just kind of see what your LO would like to do. I'd start with cutting one nap back to ~45 minutes, instead of the 30...if you feel that's better. You're just going to have to cut back on the daytime sleep somewhere, and you shouldn't go right to one long nap until A time is closer to ~5h. As you can see, our days are between 13-13h15 long. During the 2-1, this is fairly common; but LO's day shouldn't be longer than 13.5h.
If I wake him up early from either nap, it means that he doesnt get his full A time and then wont sleep well at night?
Not necessarily. You just want to make sure that you shorten his A time after the shorter nap so that he doesn't get OT.
HTH a bit!