diff --git a/src/iso19111/operation/singleoperation.cpp b/src/iso19111/operation/singleoperation.cpp
index 22400f6fb0..a0016b9003 100644
--- a/src/iso19111/operation/singleoperation.cpp
+++ b/src/iso19111/operation/singleoperation.cpp
@@ -3482,8 +3482,28 @@ bool SingleOperation::exportToPROJStringGeneric(
 
         auto sourceCRSGeod =
             dynamic_cast<const crs::GeodeticCRS *>(sourceCRS().get());
+        if (!sourceCRSGeod) {
+            auto sourceCRSCompound =
+                dynamic_cast<const crs::CompoundCRS *>(sourceCRS().get());
+            if (sourceCRSCompound) {
+                sourceCRSGeod = dynamic_cast<const crs::GeodeticCRS *>(
+                    sourceCRSCompound->componentReferenceSystems()
+                        .front()
+                        .get());
+            }
+        }
         auto targetCRSGeod =
             dynamic_cast<const crs::GeodeticCRS *>(targetCRS().get());
+        if (!targetCRSGeod) {
+            auto targetCRSCompound =
+                dynamic_cast<const crs::CompoundCRS *>(targetCRS().get());
+            if (targetCRSCompound) {
+                targetCRSGeod = dynamic_cast<const crs::GeodeticCRS *>(
+                    targetCRSCompound->componentReferenceSystems()
+                        .front()
+                        .get());
+            }
+        }
         if (sourceCRSGeod && targetCRSGeod) {
             auto sourceCRSGeog =
                 dynamic_cast<const crs::GeographicCRS *>(sourceCRSGeod);
diff --git a/test/cli/test_projinfo.yaml b/test/cli/test_projinfo.yaml
index d1e20b413c..f4760317eb 100644
--- a/test/cli/test_projinfo.yaml
+++ b/test/cli/test_projinfo.yaml
@@ -1853,3 +1853,17 @@ tests:
       +step +inv +proj=cart +ellps=WGS84
       +step +proj=unitconvert +xy_in=rad +xy_out=deg
       +step +proj=axisswap +order=2,1
+- comment: >
+   Test 'WGS 84 (Gxxx) + EGM2008 height' to 'WGS 84 (Gyyy) + EGM2008 height'
+  args: -s "WGS 84 (G1150) + EGM2008 height" -t "WGS 84 (G1674) + EGM2008 height" -o PROJ -q
+  out: |
+    +proj=pipeline
+      +step +proj=axisswap +order=2,1
+      +step +proj=unitconvert +xy_in=deg +xy_out=rad
+      +step +proj=cart +ellps=WGS84
+      +step +proj=helmert +x=-0.0024 +y=0.0016 +z=0.0232 +rx=-0.00027 +ry=0.00027
+            +rz=-0.00038 +s=0.00208 +dx=-0.0001 +dy=-0.0001 +dz=0.0018 +drx=0 +dry=0
+            +drz=0 +ds=-8e-05 +t_epoch=2005 +convention=coordinate_frame
+      +step +inv +proj=cart +ellps=WGS84
+      +step +proj=unitconvert +xy_in=rad +xy_out=deg
+      +step +proj=axisswap +order=2,1