Iv used blankets from the start
My twins never liked to be swaddled so up to 2 months I would tuck it around them. Now they sleep in their crib in their room instead of the pack and play next to my bed and they both sleep with a blanket. They are 4 months old now. They also sleep with a receiving blanket that they hold onto with their pacifiers. My girls will not sleep without the blanket to hold. That's just what works for us whether it's good or bad I follow my instincts.