Where does fastai looks for downloaded pre weights

I face a strange issue while performing below activities

  1. I download the weights of say resnet101
  2. I train the model and save the weights under working path/model
  3. I download another model weights resnext this time…
  4. I start the training but i get an error while loading of weights
  5. I delete the old weights and then start the training it works this time.

Does first point of look for pretrained weights is working dir/models ?
If yes how can i make sure it always looks for pretrained weights while training in freeze or unfreeze mode in default path where weight are downloaded.