diff --git a/reg_tests/CTestList.cmake b/reg_tests/CTestList.cmake
index 00d14710d8..42f991f28e 100644
--- a/reg_tests/CTestList.cmake
+++ b/reg_tests/CTestList.cmake
@@ -319,6 +319,7 @@ of_regression_linear("5MW_Land_BD_Linear"           "openfast;linear;beamdyn;ser
 of_regression_linear("5MW_Land_BD_Linear_Aero"      "openfast;linear;beamdyn;servodyn;aerodyn")
 of_regression_linear("5MW_OC4Semi_Linear"           "openfast;linear;hydrodyn;servodyn;map")
 of_regression_linear("5MW_OC4Semi_MD_Linear"        "openfast;linear;hydrodyn;servodyn;moordyn")
+of_regression_linear("5MW_OC3Mnpl_Linear"        "openfast;linear;hydrodyn;servodyn;moordyn")
 of_regression_linear("StC_test_OC4Semi_Linear_Nac"  "openfast;linear;servodyn;stc")
 of_regression_linear("StC_test_OC4Semi_Linear_Tow"  "openfast;linear;servodyn;stc")
 of_regression_linear("5MW_OC3Spar_Linear"           "openfast;linear;map;hydrodyn")
diff --git a/reg_tests/executeOpenfastLinearRegressionCase.py b/reg_tests/executeOpenfastLinearRegressionCase.py
index 289abe292c..fbdbe635e3 100644
--- a/reg_tests/executeOpenfastLinearRegressionCase.py
+++ b/reg_tests/executeOpenfastLinearRegressionCase.py
@@ -182,9 +182,14 @@ def indent(msg, sindent='\t'):
     for i, f in enumerate(localOutFiles):
         local_file = os.path.join(testBuildDirectory, f)
         baseline_file = os.path.join(targetOutputDirectory, f)
+        # Set a prefix for all errors to identify where it comes from
+        basename = os.path.splitext(os.path.basename(local_file))[0]
+        ext2 = os.path.splitext(basename)[1][1:]  #+'.lin' # '.1' or '.AD' '.BD'
+        errPrefix = CasePrefix[:-1]+ext2+': '
+
         if verbose:
-            print(CasePrefix+'ref:', baseline_file)
-            print(CasePrefix+'new:', local_file)
+            print(errPrefix+'ref:', baseline_file)
+            print(errPrefix+'new:', local_file)
 
         # verify both files have the same number of lines
         local_file_line_count = file_line_count(local_file)
@@ -228,8 +233,8 @@ def indent(msg, sindent='\t'):
                 v_loc = np.diag(Lambda)
 
                 if verbose:
-                    print(CasePrefix+'val_ref:', v_bas[:7])
-                    print(CasePrefix+'val_new:', v_loc[:7])
+                    print(errPrefix+'val_ref:', v_bas[:7])
+                    print(errPrefix+'val_new:', v_loc[:7])
                 try:
                     np.testing.assert_allclose(v_bas[:10], v_loc[:10], rtol=rtol_f, atol=atol_f)
                 except Exception as e:
@@ -237,10 +242,10 @@ def indent(msg, sindent='\t'):
             else:
 
                 #if verbose:
-                print(CasePrefix+'freq_ref:', np.around(freq_bas[:10]    ,5), '[Hz]')
-                print(CasePrefix+'freq_new:', np.around(freq_loc[:10]    ,5), '[Hz]')
-                print(CasePrefix+'damp_ref:', np.around(zeta_bas[:10]*100,5), '[%]')
-                print(CasePrefix+'damp_new:', np.around(zeta_loc[:10]*100,5), '[%]')
+                print(errPrefix+'freq_ref:', np.around(freq_bas[:10]    ,5), '[Hz]')
+                print(errPrefix+'freq_new:', np.around(freq_loc[:10]    ,5), '[Hz]')
+                print(errPrefix+'damp_ref:', np.around(zeta_bas[:10]*100,5), '[%]')
+                print(errPrefix+'damp_new:', np.around(zeta_loc[:10]*100,5), '[%]')
 
                 try:
                     np.testing.assert_allclose(freq_loc[:10], freq_bas[:10], rtol=rtol_f, atol=atol_f)
@@ -266,7 +271,7 @@ def indent(msg, sindent='\t'):
             if k not in KEYS or v is None:
                 continue
             if verbose:
-                print(CasePrefix+'key:', k)
+                print(errPrefix+'key:', k)
             # Arrays
             Mloc=np.atleast_2d(floc[k])
             Mbas=np.atleast_2d(fbas[k])
diff --git a/reg_tests/r-test b/reg_tests/r-test
index e281d0529e..39123bd8b5 160000
--- a/reg_tests/r-test
+++ b/reg_tests/r-test
@@ -1 +1 @@
-Subproject commit e281d0529e10086f1ad3a2a7da8514d56bf8be84
+Subproject commit 39123bd8b52e37de3392da51b53fb888e316c275