My girls both dropped down to one sleep at about 12mths old. I made sure I gave them an early lunch (like 11/11:30am) then they would have a great sleep.
DD#1 in particular ended up going from two half hour naps to a 2hr nap in the middle of the day! It worked much better.

No harm in giving it a go? You can always go back to trying the arvo nap too