sorry for the late reply, the site went down for a while!
sounds like he is starting the 2 to 1 nap switch. now that doesnt mean he is anywhere near being on one nap yet but you will need to do some tweaking as you are running out of hours in the day as his A time increases.
there are two approaches:
1) gradually shorten the am nap, and nudge the second nap slightly earlier (eg. am nap 10 mins shorter, offer second nap 10mins earlier). eventually the am nap will become a catnap and then disappear. this tends to suit LO who get sleepy very early in the morning and who like a long last A time before bed.
2) nudge the first nap slightly later and gradually shorten the pm nap which will eventually become a catnap and disappear. this tends to suit LOs who like a long first A time and short last A time before bed and also those who hate to be woken from naps. (this is the approach i did with my LO)
is he typically an 11/11.5/12 hr sleeper at night? you would want to aim for a minimum of 11hrs night sleep, so for now i would suggest shaving 15 mins off of whichever nap you choose and making bedtime 8pm (based on a 7am wake up).
here are a few links which may be helpful:
http://babywhispererforums.com/index.php?topic=145344.0http://babywhispererforums.com/index.php?topic=95670.0HTH
kirry