docs: update NEWS

NEWS.md

@@ -6,19 +6,25 @@
 
 	- Ambiguous codes (e.g., `"AD1"`, which corresponds to a SAQN and locally managed site) will error. In this instance, users should define `source` manually.
 
+	- Incorrect codes not found in `importMeta()` will error if `importUKAQ()` is left to assign the `source`.
+
 	- When `data_type` is one of the aggregate types (e.g., `"annual"`) and a `site` isn't defined, a `source` must be provided.
 
 	- It is likely *slightly* slower for the function to assign `source` itself than for users to specify it themselves.
 
+- The `formula.label` argument of `polarPlot()` will now control whether concentration information is printed when `statistic = "cpf"`.
+
 ## Bug fixes
 
 - Fixed an issue wherein `importUKAQ()` would drop sites if importing from `local` sites *and* another network.
 
+- `polarCluster()` will no longer error with multiple `pollutant`s and a single `n.clusters`.
+
 # openair 2.18-2
 
 ## New Features
 
-- add option to `corPlot` to carry through "use" option in `cor`.
+- add option to `corPlot()` to carry through "use" option in `cor`.
 
 ## Bug fixes