The earlier you move the better! You can start collecting the new Analytics data now.
Links
https://support.google.com/analytics/answer/10089681
Using the step by step guide to moving
Once a Google Analytics 4 property is created and connected, the Setup Assistant can automate some required setup steps and help you track your progress. For example, the Setup Assistant lets you select the goals you want to import to Google Analytics 4, copy desired Google Ads links and audiences, and add users who have access to your current property.
The best Google Analytics 4 setup comes from following the steps above to create a customized property tailored to your needs. The earlier you do this, the more historical data and insights you will have in Google Analytics 4. For example, SunCorp, one of Australia’s largest financial services brands, prioritized setting up Google Analytics 4 to build a base of historical insights.
https://support.google.com/analytics/answer/10110290
Step by step guide to moving Analytics
https://support.google.com/analytics/answer/10759417
Turn insights into ROI with Google Analytics
https://blog.google/products/marketingplatform/analytics/turn-insights-roi-google-analytics/
Google Analytics will be going away and moving to v4
https://support.google.com/analytics/answer/11583528
Check which type of analytics property you are using
https://support.google.com/analytics/answer/11583832
Web Notes and Ramblings 