While there is no specific time that you have to stop swaddling your newborn or infant, we recommend that after around one month of age, babies should be swaddled ONLY for naps and night-time so as to increase mobility and allow babies to begin to learn about what is around them through movement and touch, while awake.
At around 6 weeks of age, we suggest parents leave one arm out of the swaddle at naps and night-time, to allow the infant to use their hand to self sooth if they wish to and at around 2.5 to 3 months of age is a good time to begin to leave both arms out.
While there are no really big reasons you need to stop swaddling at that point, we do find that the swaddle itself can become a sleep crutch, preventing babies from learning to self settle, not to mention the frustration of trying to keep baby Houdini swaddled through the night. The next thing you know, you are up ten times nightly again, to replace it because baby now (thinks he) can not sleep without.
Good luck & Live WELL.