Try stretching out her awake time by fifteen minute increments over the course of a few weeks to stretch out that morning awake time. She's beginning to balk at the two naps, but as above poster said, the transition to one is long. My son is fourteen months, has made the transition recently, and will go a good three hours midday now. I used to take him for a short car ride or walk in the late afternoon/early evening if it was clear he needed a catnap and wasn't going to make it to bedtime. He simply howled at being put down in his bed for the catnap and since I knew it was temporary, would wiggle in a quicky nap on the go as needed.
Also, consider teeth and walking milestones as possible disruptions, but the naps are definetly a factor too.
Keep in mind you may wind up readjusting bedtimes, etc. I always base naps and bedtime on time awake and fluctuate as necessary.
Best.
