Warnings: Incompatible shape with model variable

I am trying to train the ssd_mobilenet_v2_coco_2018 model with my custom dataset with 4 classes. I have used the object_detection/model_main.py file for training from object detection. ssd_mobilenet_v2_coco_2018_03_29/model.ckpt pre-trained model been used for fine-tuned. During training following warnings i received. May i know what does it means.

W0404 11:14:14.462951 140586358265664 variables_helper.py:154] Variable [FeatureExtractor/MobilenetV2/layer_19_2_Conv2d_2_3x3_s2_512/weights] is available in checkpoint, but has an incompatible shape with model variable. Checkpoint shape: [[1, 1, 256, 512]], model variable shape: [[3, 3, 256, 512]]. This variable will not be initialized from the checkpoint.
W0404 11:14:14.463244 140586358265664 variables_helper.py:154] Variable [FeatureExtractor/MobilenetV2/layer_19_2_Conv2d_3_3x3_s2_256/weights] is available in checkpoint, but has an incompatible shape with model variable. Checkpoint shape: [[1, 1, 128, 256]], model variable shape: [[3, 3, 128, 256]]. This variable will not be initialized from the checkpoint.
W0404 11:14:14.463427 140586358265664 variables_helper.py:154] Variable [FeatureExtractor/MobilenetV2/layer_19_2_Conv2d_4_3x3_s2_256/weights] is available in checkpoint, but has an incompatible shape with model variable. Checkpoint shape: [[1, 1, 128, 256]], model variable shape: [[3, 3, 128, 256]]. This variable will not be initialized from the checkpoint.
W0404 11:14:14.463576 140586358265664 variables_helper.py:154] Variable [FeatureExtractor/MobilenetV2/layer_19_2_Conv2d_5_3x3_s2_128/weights] is available in checkpoint, but has an incompatible shape with model variable. Checkpoint shape: [[1, 1, 64, 128]], model variable shape: [[3, 3, 64, 128]]. This variable will not be initialized from the checkpoint.
WARNING:tensorflow:From 

OS: Ubuntu 18.04
Framework: Tensorflow 1.14.0
Orignal image size: 1820x940
Config File: Following items are changed in config file remaining are same as default.

num_classes: 4
fine_tune_checkpoint: "ssd_mobilenet_v2_coco_2018_03_29/model.ckpt"
fine_tune_checkpoint_type:  "detection"
load_all_detection_checkpoint_vars: false