If you go to this page :
https://www.flyingblue.com/en/progra.../tier-benefits
If you click the Lounge Access dropdown and then click on the numbers 3, 4, 6, 19, and 30 you will find:
- Paragraph numbered 30 says: A 3-hour pre-flight lounge access limit applies to SkyTeam lounges. Flying Blue Gold, Platinum, and Ultimate members (and their guests) can continue to access Air France and KLM lounges earlier than 3 hours before departure.
I guess that doesn't apply to me as my status is with Delta and not KLM. - Paragraph numbered 4 is the only one I could find referencing connections:
Gold and Platinum members and one guest benefit from complimentary access to lounges when travelling on the exact same flight operated by Air France, KLM, China Southern Airways or a SkyTeam partner (including connections to/from an international SkyTeam partner flight)