tbf: Update the timing advance for the new tlli based on the old one
diff --git a/src/ta.h b/src/ta.h
index 8508acb..9b64280 100644
--- a/src/ta.h
+++ b/src/ta.h
@@ -29,6 +29,7 @@
 public:
 	TimingAdvance();
 
+	int update(uint32_t old_tlli, uint32_t new_tlli, uint8_t ta);
 	int remember(uint32_t tlli, uint8_t ta);
 	int recall(uint32_t tlli);
 	int flush();