diff --git a/src/libslic3r/PrintApply.cpp b/src/libslic3r/PrintApply.cpp
index 73da62d38..0c95d1d24 100644
--- a/src/libslic3r/PrintApply.cpp
+++ b/src/libslic3r/PrintApply.cpp
@@ -1424,7 +1424,7 @@ Print::ApplyStatus Print::apply(const Model &model, DynamicPrintConfig new_full_
 
         update_apply_status(this->invalidate_step(psGCodeExport));
 
-        if (full_config_diff.empty()) {
+        if (!full_config_diff.empty()) {
             //BBS: previous empty
             BOOST_LOG_TRIVIAL(info) << __FUNCTION__ << boost::format(" %1%: full_config_diff previous empty, need to apply now.")%__LINE__;
 
diff --git a/src/libslic3r/PrintConfig.hpp b/src/libslic3r/PrintConfig.hpp
index d3f7ee2de..78ea46620 100644
--- a/src/libslic3r/PrintConfig.hpp
+++ b/src/libslic3r/PrintConfig.hpp
@@ -636,7 +636,7 @@ PRINT_CONFIG_CLASS_DEFINE(
     ((ConfigOptionFloat,               support_speed))
     ((ConfigOptionEnum<SupportMaterialStyle>, support_style))
     // BBS
-    ((ConfigOptionBool,                independent_support_layer_height))
+    //((ConfigOptionBool,                independent_support_layer_height))
     ((ConfigOptionBool,                thick_bridges))
     // Overhang angle threshold.
     ((ConfigOptionInt,                 support_threshold_angle))
@@ -902,7 +902,8 @@ PRINT_CONFIG_CLASS_DERIVED_DEFINE(
     ((ConfigOptionBool,               has_prime_tower))
     ((ConfigOptionFloat,              nozzle_volume))
     ((ConfigOptionEnum<TimelapseType>,    timelapse_type))
-
+    // BBS: move from PrintObjectConfig
+    ((ConfigOptionBool, independent_support_layer_height))
 )
 
 // This object is mapped to Perl as Slic3r::Config::Full.
diff --git a/src/libslic3r/PrintObject.cpp b/src/libslic3r/PrintObject.cpp
index 775f27484..eec4e5663 100644
--- a/src/libslic3r/PrintObject.cpp
+++ b/src/libslic3r/PrintObject.cpp
@@ -738,7 +738,7 @@ bool PrintObject::invalidate_state_by_config_options(
             || opt_key == "support_style"
             || opt_key == "support_object_xy_distance"
             || opt_key == "support_base_pattern_spacing"
-            || opt_key == "independent_support_layer_height" // BBS
+            //|| opt_key == "independent_support_layer_height" // BBS
             || opt_key == "support_threshold_angle"
             || opt_key == "raft_expansion"
             || opt_key == "raft_first_layer_density"
diff --git a/src/libslic3r/Slicing.cpp b/src/libslic3r/Slicing.cpp
index 1fb78a180..58bc4b150 100644
--- a/src/libslic3r/Slicing.cpp
+++ b/src/libslic3r/Slicing.cpp
@@ -119,7 +119,7 @@ SlicingParameters SlicingParameters::create_from_config(
         if (params.gap_object_support <= 0)
             params.gap_object_support = params.gap_support_object;
 
-        if (!object_config.independent_support_layer_height) {
+        if (!print_config.independent_support_layer_height) {
             params.gap_raft_object = std::round(params.gap_raft_object / object_config.layer_height + EPSILON) * object_config.layer_height;
             params.gap_object_support = std::round(params.gap_object_support / object_config.layer_height + EPSILON) * object_config.layer_height;
             params.gap_support_object = std::round(params.gap_support_object / object_config.layer_height + EPSILON) * object_config.layer_height;
diff --git a/src/libslic3r/SupportMaterial.cpp b/src/libslic3r/SupportMaterial.cpp
index 11305cfc7..fbbecdb45 100644
--- a/src/libslic3r/SupportMaterial.cpp
+++ b/src/libslic3r/SupportMaterial.cpp
@@ -1839,7 +1839,7 @@ static inline std::pair<PrintObjectSupportMaterial::MyLayer*, PrintObjectSupport
         bottom_z = (layer_id == 1) ? slicing_params.object_print_z_min : layer.lower_layer->lower_layer->print_z;
     } else {
         print_z  = layer.bottom_z() - slicing_params.gap_support_object;
-        height   = object_config.independent_support_layer_height ? 0. : object_config.layer_height;
+        height   = print_config.independent_support_layer_height ? 0. : object_config.layer_height;
         bottom_z = print_z - height;
         // Ignore this contact area if it's too low.
         // Don't want to print a layer below the first layer height as it may not stick well.
@@ -1870,7 +1870,7 @@ static inline std::pair<PrintObjectSupportMaterial::MyLayer*, PrintObjectSupport
                 bridging_height += region->region().bridging_height_avg(print_config);
             bridging_height /= coordf_t(layer.regions().size());
             // BBS: align bridging height
-            if (!object_config.independent_support_layer_height)
+            if (!print_config.independent_support_layer_height)
                 bridging_height = std::ceil(bridging_height / object_config.layer_height - EPSILON) * object_config.layer_height;
             coordf_t bridging_print_z = layer.print_z - bridging_height - slicing_params.gap_support_object;
             if (bridging_print_z >= min_print_z) {
@@ -1890,7 +1890,7 @@ static inline std::pair<PrintObjectSupportMaterial::MyLayer*, PrintObjectSupport
                     } else {
                         // BBS: if independent_support_layer_height is not enabled, the support layer_height should be the same as layer height.
                         // Note that for this case, adaptive layer height must be disabled.
-                        bridging_layer->height = object_config.independent_support_layer_height ? 0. : object_config.layer_height;
+                        bridging_layer->height = print_config.independent_support_layer_height ? 0. : object_config.layer_height;
                         // Don't know the height yet.
                         bridging_layer->bottom_z = bridging_print_z - bridging_layer->height;
                     }
@@ -2423,7 +2423,7 @@ static inline PrintObjectSupportMaterial::MyLayer* detect_bottom_contacts(
     // top shapes so this can be done here
     //FIXME calculate layer height based on the actual thickness of the layer:
     // If the layer is extruded with no bridging flow, support just the normal extrusions.
-    layer_new.height = slicing_params.soluble_interface || !object.config().independent_support_layer_height ?
+    layer_new.height = slicing_params.soluble_interface || !object.print()->config().independent_support_layer_height ?
         // Align the interface layer with the object's layer height.
         layer.upper_layer->height :
         // Place a bridge flow interface layer or the normal flow interface layer over the top surface.
diff --git a/src/libslic3r/SupportMaterial.hpp b/src/libslic3r/SupportMaterial.hpp
index 7bb60dd53..fd378d93b 100644
--- a/src/libslic3r/SupportMaterial.hpp
+++ b/src/libslic3r/SupportMaterial.hpp
@@ -161,7 +161,7 @@ public:
 	bool 		has_support()				const { return m_object_config->enable_support.value || m_object_config->enforce_support_layers; }
 	bool 		build_plate_only() 			const { return this->has_support() && m_object_config->support_on_build_plate_only.value; }
 	// BBS
-	bool 		synchronize_layers()		const { return /*m_slicing_params.soluble_interface && */!m_object_config->independent_support_layer_height.value; }
+	bool 		synchronize_layers()		const { return /*m_slicing_params.soluble_interface && */!m_print_config->independent_support_layer_height.value; }
 	bool 		has_contact_loops() 		const { return m_object_config->support_interface_loop_pattern.value; }
 
 	// Generate support material for the object.
diff --git a/src/libslic3r/TreeSupport.cpp b/src/libslic3r/TreeSupport.cpp
index 01374902e..1450ec4db 100644
--- a/src/libslic3r/TreeSupport.cpp
+++ b/src/libslic3r/TreeSupport.cpp
@@ -2818,8 +2818,9 @@ void TreeSupport::adjust_layer_heights(std::vector<std::vector<Node*>>& contact_
     if (contact_nodes.empty())
         return;
 
+    const PrintConfig& print_config = m_object->print()->config();
     const PrintObjectConfig& config = m_object->config();
-    if (!config.independent_support_layer_height) {
+    if (!print_config.independent_support_layer_height) {
         for (int layer_nr = 0; layer_nr < contact_nodes.size(); layer_nr++) {
             std::vector<Node*>& curr_layer_nodes = contact_nodes[layer_nr];
             for (Node* node : curr_layer_nodes) {