diff --git a/specific/configuration/flexible_acquisition.cpp b/specific/configuration/flexible_acquisition.cpp
index 4d95cb7a8561786645357ae5fd77f9fba3845186..e26cde942de20e79ba9b5720d7dbfa5bcc2d3c35 100644
--- a/specific/configuration/flexible_acquisition.cpp
+++ b/specific/configuration/flexible_acquisition.cpp
@@ -112,6 +112,11 @@ namespace flexible_acquisition
           _model_known[Support::BLK] = _supersurface[Support::BLK] | _subsurface[Support::BLK];
           _model_known[Support::BND] = _supersurface[Support::BND] | _subsurface[Support::BND];
         }
+        else if (unknownRegion == "all")
+        {
+          _model_unknown[Support::BLK] = _supersurface[Support::BLK] | _subsurface[Support::BLK];
+          _model_unknown[Support::BND] = _supersurface[Support::BND] | _subsurface[Support::BND];
+        }
         else {
             throw Exception("Invalid unknown region type: " + unknownRegion);
         }