New custody schedule starting Monday and I'm anxious as hell

The new court order went through and we're switching to 50/50 custody starting this coming Monday. Been with the kids full time for 2 years so going from 7 days to 3-4 days per week is hitting different. My ex and I aren't on the best terms so texting about logistics feels tense. Anyone have advice on how to keep things civil and business-like when the other parent drives you crazy? Also how long does it take the kids to adjust to switching back and forth?