pre-announcement of Sptember meetup in index.md

Author: sunito

index.md

@@ -2,7 +2,7 @@
 
 ## Upcoming events
 
-Our next meetup will be on **June 11th, 2026** at 5 pm.     
+Our next meetup will probably be on **September 15th, 2026** at 6:30 pm.     
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