Update proposal.md

Author: sadiejay

pages/proposal.md

@@ -17,7 +17,7 @@ files:
 
 We are now accepting proposals for The Opportunity Project 2025 sprint cycle!
 
-**All 2025 sprints must begin by the week of September 15, 2025.**
+**We will be reviewing submissions on a rolling basis. All 2025 sprints must begin by the week of September 15, 2025.**
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 - Before you start drafting your sprint topic proposal, please review the guidelines below.