Correct release notes now we are not type checking identifier columns

Author: arthompson

docs/release-notes/11.0.1.md

@@ -4,22 +4,24 @@ Release date: 2023-03-08
 
 ## Synopsis
 
-Remove type validation for columns which are only used for data grouping.
+Remove type validation for columns which are only used for data identification.
 
 ## Changes
 
-Previously, columns only used for data grouping in methods were only allowed
-to contain data of StringType. This doesn't really make sense since these
-columns are only used in group by clauses and thus the type doesn't matter.
-This release removes these restrictions.
+Previously, columns used for data identification (both individual
+contributors and data grouping) in methods were only allowed to contain
+strings. This doesn't really make sense since these identification columns
+are only used in contexts where the type doesn't matter. This release
+removes these restrictions.
 
 ## Notes
 
 The effected methods and associated columns (named by method parameter) are
 as follows:
 
-* Imputation - `grouping_col`
-* HT Ratio Estimation - `strata_col` and `calibration_group_col`
-* Winsorisation - `grouping_col`
+* Imputation - `reference_col` and `grouping_col`
+* HT Ratio Estimation - `unique_identifier_col`, `strata_col` and
+  `calibration_group_col`
+* Winsorisation - `reference_col` and `grouping_col`
 
 This release does not have any impact on method outputs.