DS is 5.5 months and I'm wondering what signs to look for and when others made the transition.

For the past week or so he's taken two shorter naps (about 35-50 minutes) and one longer nap (1-1.5 hours...sometimes even two hours!). We typically put him down about 2 hours from his last waking...should we stretch that time out and consolidate his naps into two?

How did you transition and how did you know it was time?