At 5.5 months we're usually looking at around 2.25 hours. 2h30 was too long.
The yawning straight out of bed is kind of normal. NOt sure why they do that? Guess it's kind of like us -- just trying to wake up! LOL! You might also look into changing venues so that he's not bored as well. Once they get to this age they can really start to need more stimulation during their A times. They are approaching mobility milestones -- sitting up, starting to learn to crawl, etc. -- and so they crave change and new stuff.
Try 2h15 and see what happens!
Alexsandersmom -- I need you to start a new thread as I the 2 are diverging too much. I also like twin mommies to have their own threads b/c you guys cna help one another so much!