diff --git a/cpp/include/raft/spatial/knn/detail/ball_cover/registers-inl.cuh b/cpp/include/raft/spatial/knn/detail/ball_cover/registers-inl.cuh
index 0337f6891f..71f9f7c492 100644
--- a/cpp/include/raft/spatial/knn/detail/ball_cover/registers-inl.cuh
+++ b/cpp/include/raft/spatial/knn/detail/ball_cover/registers-inl.cuh
@@ -157,7 +157,7 @@ template <typename value_idx,
           int thread_q = 2,
           int tpb      = 128,
           int col_q    = 2>
-RAFT_KERNEL compute_final_dists_registers(const value_t* X_index,
+RAFT_KERNEL compute_final_dists_registers(const value_t* X_reordered,
                                           const value_t* X,
                                           const value_int n_cols,
                                           bitset_type* bitset,
@@ -238,7 +238,7 @@ RAFT_KERNEL compute_final_dists_registers(const value_t* X_index,
         // the closest k neighbors, compute it and add to k-select
         value_t dist = std::numeric_limits<value_t>::max();
         if (z <= heap.warpKTop) {
-          const value_t* y_ptr = X_index + (n_cols * cur_candidate_ind);
+          const value_t* y_ptr = X_reordered + (n_cols * (R_start_offset + i));
           value_t local_y_ptr[col_q];
           for (value_int j = 0; j < n_cols; ++j) {
             local_y_ptr[j] = y_ptr[j];
@@ -267,7 +267,7 @@ RAFT_KERNEL compute_final_dists_registers(const value_t* X_index,
         // the closest k neighbors, compute it and add to k-select
         value_t dist = std::numeric_limits<value_t>::max();
         if (z <= heap.warpKTop) {
-          const value_t* y_ptr = X_index + (n_cols * cur_candidate_ind);
+          const value_t* y_ptr = X_reordered + (n_cols * (R_start_offset + i));
           value_t local_y_ptr[col_q];
           for (value_int j = 0; j < n_cols; ++j) {
             local_y_ptr[j] = y_ptr[j];
@@ -313,7 +313,7 @@ template <typename value_idx = std::int64_t,
           int col_q          = 2,
           typename value_int = std::uint32_t,
           typename distance_func>
-RAFT_KERNEL block_rbc_kernel_registers(const value_t* X_index,
+RAFT_KERNEL block_rbc_kernel_registers(const value_t* X_reordered,
                                        const value_t* X,
                                        value_int n_cols,  // n_cols should be 2 or 3 dims
                                        const value_idx* R_knn_inds,
@@ -408,7 +408,7 @@ RAFT_KERNEL block_rbc_kernel_registers(const value_t* X_index,
       value_t dist = std::numeric_limits<value_t>::max();
 
       if (z <= heap.warpKTop) {
-        const value_t* y_ptr = X_index + (n_cols * cur_candidate_ind);
+        const value_t* y_ptr = X_reordered + (n_cols * (R_start_offset + i));
         value_t local_y_ptr[col_q];
         for (value_int j = 0; j < n_cols; ++j) {
           local_y_ptr[j] = y_ptr[j];
@@ -433,7 +433,7 @@ RAFT_KERNEL block_rbc_kernel_registers(const value_t* X_index,
       value_t dist = std::numeric_limits<value_t>::max();
 
       if (z <= heap.warpKTop) {
-        const value_t* y_ptr = X_index + (n_cols * cur_candidate_ind);
+        const value_t* y_ptr = X_reordered + (n_cols * (R_start_offset + i));
         value_t local_y_ptr[col_q];
         for (value_int j = 0; j < n_cols; ++j) {
           local_y_ptr[j] = y_ptr[j];
@@ -1013,7 +1013,7 @@ void rbc_low_dim_pass_one(raft::resources const& handle,
   if (k <= 32)
     block_rbc_kernel_registers<value_idx, value_t, 32, 2, 128, dims, value_int>
       <<<n_query_rows, 128, 0, resource::get_cuda_stream(handle)>>>(
-        index.get_X().data_handle(),
+        index.get_X_reordered().data_handle(),
         query,
         index.n,
         R_knn_inds,
@@ -1033,7 +1033,7 @@ void rbc_low_dim_pass_one(raft::resources const& handle,
   else if (k <= 64)
     block_rbc_kernel_registers<value_idx, value_t, 64, 3, 128, 2, value_int>
       <<<n_query_rows, 128, 0, resource::get_cuda_stream(handle)>>>(
-        index.get_X().data_handle(),
+        index.get_X_reordered().data_handle(),
         query,
         index.n,
         R_knn_inds,
@@ -1052,7 +1052,7 @@ void rbc_low_dim_pass_one(raft::resources const& handle,
   else if (k <= 128)
     block_rbc_kernel_registers<value_idx, value_t, 128, 3, 128, dims, value_int>
       <<<n_query_rows, 128, 0, resource::get_cuda_stream(handle)>>>(
-        index.get_X().data_handle(),
+        index.get_X_reordered().data_handle(),
         query,
         index.n,
         R_knn_inds,
@@ -1072,7 +1072,7 @@ void rbc_low_dim_pass_one(raft::resources const& handle,
   else if (k <= 256)
     block_rbc_kernel_registers<value_idx, value_t, 256, 4, 128, dims, value_int>
       <<<n_query_rows, 128, 0, resource::get_cuda_stream(handle)>>>(
-        index.get_X().data_handle(),
+        index.get_X_reordered().data_handle(),
         query,
         index.n,
         R_knn_inds,
@@ -1092,7 +1092,7 @@ void rbc_low_dim_pass_one(raft::resources const& handle,
   else if (k <= 512)
     block_rbc_kernel_registers<value_idx, value_t, 512, 8, 64, dims, value_int>
       <<<n_query_rows, 64, 0, resource::get_cuda_stream(handle)>>>(
-        index.get_X().data_handle(),
+        index.get_X_reordered().data_handle(),
         query,
         index.n,
         R_knn_inds,
@@ -1112,7 +1112,7 @@ void rbc_low_dim_pass_one(raft::resources const& handle,
   else if (k <= 1024)
     block_rbc_kernel_registers<value_idx, value_t, 1024, 8, 64, dims, value_int>
       <<<n_query_rows, 64, 0, resource::get_cuda_stream(handle)>>>(
-        index.get_X().data_handle(),
+        index.get_X_reordered().data_handle(),
         query,
         index.n,
         R_knn_inds,
@@ -1182,7 +1182,7 @@ void rbc_low_dim_pass_two(raft::resources const& handle,
                                   128,
                                   dims>
       <<<n_query_rows, 128, 0, resource::get_cuda_stream(handle)>>>(
-        index.get_X().data_handle(),
+        index.get_X_reordered().data_handle(),
         query,
         index.n,
         bitset.data(),
@@ -1208,7 +1208,7 @@ void rbc_low_dim_pass_two(raft::resources const& handle,
                                   128,
                                   dims>
       <<<n_query_rows, 128, 0, resource::get_cuda_stream(handle)>>>(
-        index.get_X().data_handle(),
+        index.get_X_reordered().data_handle(),
         query,
         index.n,
         bitset.data(),
@@ -1234,7 +1234,7 @@ void rbc_low_dim_pass_two(raft::resources const& handle,
                                   128,
                                   dims>
       <<<n_query_rows, 128, 0, resource::get_cuda_stream(handle)>>>(
-        index.get_X().data_handle(),
+        index.get_X_reordered().data_handle(),
         query,
         index.n,
         bitset.data(),
@@ -1260,7 +1260,7 @@ void rbc_low_dim_pass_two(raft::resources const& handle,
                                   128,
                                   dims>
       <<<n_query_rows, 128, 0, resource::get_cuda_stream(handle)>>>(
-        index.get_X().data_handle(),
+        index.get_X_reordered().data_handle(),
         query,
         index.n,
         bitset.data(),
@@ -1285,7 +1285,7 @@ void rbc_low_dim_pass_two(raft::resources const& handle,
                                   8,
                                   64,
                                   dims><<<n_query_rows, 64, 0, resource::get_cuda_stream(handle)>>>(
-      index.get_X().data_handle(),
+      index.get_X_reordered().data_handle(),
       query,
       index.n,
       bitset.data(),
@@ -1310,7 +1310,7 @@ void rbc_low_dim_pass_two(raft::resources const& handle,
                                   8,
                                   64,
                                   dims><<<n_query_rows, 64, 0, resource::get_cuda_stream(handle)>>>(
-      index.get_X().data_handle(),
+      index.get_X_reordered().data_handle(),
       query,
       index.n,
       bitset.data(),