nap transition

lynsef

It now takes so much time/effort to get DD (4 yr in Oct) and DS1 (2 yr) down for a nap. Its exhausting and also difficult with a 3 week old. But if they dont get their nap they are holy terrors by 4 or 5 pm. They go to bed at 8-8:30 and wake up at 6:30. They have always been early risers. DD starts preschool in 3 weeks with a 745 start time so sleeping later to make up for it isnt an option. Im wondering if your LO stopped napping how long was the transition until they got used to not having it? Did you put them to bed earlier? TIA!