diff --git a/.github/workflows/build-special.yml b/.github/workflows/build-special.yml
index ef7d7723d9..96e7174aea 100644
--- a/.github/workflows/build-special.yml
+++ b/.github/workflows/build-special.yml
@@ -111,7 +111,7 @@ jobs:
         if: matrix.flag == 'deprecated'
         run: |
           echo "GTSAM_ALLOW_DEPRECATED_SINCE_V42=ON" >> $GITHUB_ENV
-          echo "Allow deprecated since version 4.1"
+          echo "Allow deprecated since version 4.2"
 
       - name: Set Use Quaternions Flag
         if: matrix.flag == 'quaternions'
diff --git a/CMakeLists.txt b/CMakeLists.txt
index b81479cb84..399259685b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -10,7 +10,7 @@ endif()
 set (GTSAM_VERSION_MAJOR 4)
 set (GTSAM_VERSION_MINOR 2)
 set (GTSAM_VERSION_PATCH 0)
-set (GTSAM_PRERELEASE_VERSION "a8")
+set (GTSAM_PRERELEASE_VERSION "")
 math (EXPR GTSAM_VERSION_NUMERIC "10000 * ${GTSAM_VERSION_MAJOR} + 100 * ${GTSAM_VERSION_MINOR} + ${GTSAM_VERSION_PATCH}")
 
 if (${GTSAM_VERSION_PATCH} EQUAL 0)
diff --git a/README.md b/README.md
index dbbba8c2b8..25b3b98ea1 100644
--- a/README.md
+++ b/README.md
@@ -55,9 +55,7 @@ Optional prerequisites - used automatically if findable by CMake:
 
 GTSAM 4 introduces several new features, most notably Expressions and a Python toolbox. It also introduces traits, a C++ technique that allows optimizing with non-GTSAM types. That opens the door to retiring geometric types such as Point2 and Point3 to pure Eigen types, which we also do. A significant change which will not trigger a compile error is that zero-initializing of Point2 and Point3 is deprecated, so please be aware that this might render functions using their default constructor incorrect.
 
-GTSAM 4 also deprecated some legacy functionality and wrongly named methods. If you are on a 4.0.X release, you can define the flag `GTSAM_ALLOW_DEPRECATED_SINCE_V4` to use the deprecated methods.
-
-GTSAM 4.1 added a new pybind wrapper, and **removed** the deprecated functionality. There is a flag `GTSAM_ALLOW_DEPRECATED_SINCE_V42` for newly deprecated methods since the 4.1 release, which is on by default, allowing anyone to just pull version 4.1 and compile.
+ There is a flag `GTSAM_ALLOW_DEPRECATED_SINCE_V42` for newly deprecated methods since the 4.2 release, which is on by default, allowing anyone to just pull version 4.2 and compile.
 
 
 ## Wrappers
diff --git a/cmake/HandleGeneralOptions.cmake b/cmake/HandleGeneralOptions.cmake
index 7c8f8533f3..00ec65ba7c 100644
--- a/cmake/HandleGeneralOptions.cmake
+++ b/cmake/HandleGeneralOptions.cmake
@@ -25,7 +25,7 @@ option(GTSAM_WITH_EIGEN_MKL_OPENMP          "Eigen, when using Intel MKL, will a
 option(GTSAM_THROW_CHEIRALITY_EXCEPTION     "Throw exception when a triangulated point is behind a camera" ON)
 option(GTSAM_BUILD_PYTHON                   "Enable/Disable building & installation of Python module with pybind11" OFF)
 option(GTSAM_INSTALL_MATLAB_TOOLBOX         "Enable/Disable installation of matlab toolbox"  OFF)
-option(GTSAM_ALLOW_DEPRECATED_SINCE_V42     "Allow use of methods/functions deprecated in GTSAM 4.1" ON)
+option(GTSAM_ALLOW_DEPRECATED_SINCE_V42     "Allow use of methods/functions deprecated in GTSAM 4.2" ON)
 option(GTSAM_SUPPORT_NESTED_DISSECTION      "Support Metis-based nested dissection" ON)
 option(GTSAM_TANGENT_PREINTEGRATION         "Use new ImuFactor with integration on tangent space" ON)
 option(GTSAM_SLOW_BUT_CORRECT_BETWEENFACTOR "Use the slower but correct version of BetweenFactor" OFF)
diff --git a/cmake/HandlePrintConfiguration.cmake b/cmake/HandlePrintConfiguration.cmake
index 04d27c27f4..5b7ef237ac 100644
--- a/cmake/HandlePrintConfiguration.cmake
+++ b/cmake/HandlePrintConfiguration.cmake
@@ -87,7 +87,7 @@ print_enabled_config(${GTSAM_USE_QUATERNIONS}             "Quaternions as defaul
 print_enabled_config(${GTSAM_ENABLE_CONSISTENCY_CHECKS}   "Runtime consistency checking    ")
 print_enabled_config(${GTSAM_ROT3_EXPMAP}                 "Rot3 retract is full ExpMap     ")
 print_enabled_config(${GTSAM_POSE3_EXPMAP}                "Pose3 retract is full ExpMap    ")
-print_enabled_config(${GTSAM_ALLOW_DEPRECATED_SINCE_V42}  "Allow features deprecated in GTSAM 4.1")
+print_enabled_config(${GTSAM_ALLOW_DEPRECATED_SINCE_V42}  "Allow features deprecated in GTSAM 4.2")
 print_enabled_config(${GTSAM_SUPPORT_NESTED_DISSECTION}   "Metis-based Nested Dissection   ")
 print_enabled_config(${GTSAM_TANGENT_PREINTEGRATION}      "Use tangent-space preintegration")
 
diff --git a/gtsam/slam/InitializePose3.cpp b/gtsam/slam/InitializePose3.cpp
index e8ec9181c0..3e2ad7ebe3 100644
--- a/gtsam/slam/InitializePose3.cpp
+++ b/gtsam/slam/InitializePose3.cpp
@@ -206,11 +206,10 @@ Values InitializePose3::computeOrientationsGradient(
   // Return correct rotations
   const Rot3& Rref = inverseRot.at(initialize::kAnchorKey); // This will be set to the identity as so far we included no prior
   Values estimateRot;
-    for (const auto key_R : inverseRot) {
+    for (const auto& key_R : inverseRot) {
     const Key& key = key_R.first;
-    const Rot3& Ri = key_R.second;
     if (key != initialize::kAnchorKey) {
-      const Rot3& R = inverseRot.at(key);
+      const Rot3& R = key_R.second;
       if(setRefFrame)
         estimateRot.insert(key, Rref.compose(R.inverse()));
       else