Hello,
there's no 'set' time when you have to stop swaddling. Tracy said around 3 months, but we didn't stop until ds was around 9 months
. At your lo's age, I'd have thought it'd still be a great help to him. Have you tried a more secure swaddle, like the Aussie swaddle, or a miracle blanket?
The pram and car seat sleeps rely on the motion, which soothe him back to sleep. They are not such refreshing sleeps, though, as all that motion will keep waking him, then re-settling him, so he won't go into such a deep sleep as he will in his cot.
HTH