His schedule looks good. It might be related to teething or SA. Have you given him anything for teething? If wi/wo is too much for him & GW is working well for you, that is, he is not playing but actually going to sleep, then I would continue doing that....
It could also be the length of the nap. Try not to let him sleep more than 2hrs cause sometimes they make up for lost sleep at night by taking a longer nap.