diff --git a/src/libslic3r/PrintObject.cpp b/src/libslic3r/PrintObject.cpp
index f373bc808..40e212c7e 100644
--- a/src/libslic3r/PrintObject.cpp
+++ b/src/libslic3r/PrintObject.cpp
@@ -1026,19 +1026,8 @@ void PrintObject::detect_surfaces_type()
             		// In non-spiral vase mode, go over all layers.
             		m_layers.size()),
             [this, spiral_mode, region_id, interface_shells, &surfaces_new](const tbb::blocked_range<size_t>& range) {
-                // If we have soluble support material, don't bridge. The overhang will be squished against a soluble layer separating
-                // the support from the print.
-                // BBS: the above logic only applys for normal(auto) support. Complete logic:
-                // 1. has support, top z distance=0 (soluble material), auto support
-                // 2. for normal(auto), bridge_no_support is off
-                // 3. for tree(auto), interface top layers=0, max bridge length=0, support_critical_regions_only=false (only in this way the bridge is fully supported)
-                bool bottom_is_fully_supported = this->has_support() && m_config.support_top_z_distance.value == 0 && is_auto(m_config.support_type.value);
-                if (m_config.support_type.value == stNormalAuto)
-                    bottom_is_fully_supported &= !m_config.bridge_no_support.value;
-                else if (m_config.support_type.value == stTreeAuto) {
-                    bottom_is_fully_supported &= (m_config.support_interface_top_layers.value > 0 && m_config.max_bridge_length.value == 0 && m_config.support_critical_regions_only.value==false);
-                }
-                SurfaceType surface_type_bottom_other = bottom_is_fully_supported ? stBottom : stBottomBridge;
+                // BBS coconut: can't set to stBottom when soluable support is used, as the support may not be actaully generated, e.g. when "on build plate only" option is enabled. See github #3507.
+                SurfaceType surface_type_bottom_other = stBottomBridge;
                 for (size_t idx_layer = range.begin(); idx_layer < range.end(); ++ idx_layer) {
                     m_print->throw_if_canceled();
                     // BOOST_LOG_TRIVIAL(trace) << "Detecting solid surfaces for region " << region_id << " and layer " << layer->print_z;