Hi,
My DD has been transitioning to one nap for a while now,she's nearly 1 now.For nearly 2 months we have been doing 20 mins at 10:30,then she has about 1 3/4 to 2 hrs from about 12:45.this has been working really well,I usually have to wake her from both naps.The 20 min catnap in the morning gets her through lunch and we have time for errands or playtime without her getting overtired.She has about 11 1/2 hrs nightsleep so I will try to keep her on this routine for a while.We did try to go cold turkey by going straight to one nap,but after a couple of weeks it resulted in short naps and 5:30am wakings,so had to do some tweaking.Haven't looked back since.Hope this help a bit.
Clare x