fix(cfp): dates (#1511)

Author: artcz

src/content/pages/programme/cfp.mdx

@@ -7,7 +7,7 @@ subtitle: A set of tips to help you put together a strong, compelling EuroPython
 
 **EuroPython 2026 Call for Proposals will be open soon!**
 
-The Call for Proposals runs from TBD to TBD.
+The Call for Proposals runs from 15 January 2026 to 15 February 2026.
 
 <Center>
 <Button url="https://programme.europython.eu/europython-2026/">Submit your proposal</Button>