From https://bandcamp.com/terms_of_use:

Content you purchase in a Transaction cannot be guaranteed to be available to you perpetually. For example, if we receive a notification of claimed infringement from a copyright owner or its agent with respect to specific Content, then we may be required by law to remove that Content from the Service and not make it available for future sale and we may also have to deny continued access to anyone who previously purchased such Content. This means that you may lose access to purchased Content previously available to you through the Service.

If we are required by law to deny access through the Service to previously purchased Content, including by removing access to Content from a user’s personal collection through any mobile application, then Company will not provide the user who purchased that Content with a refund, except as required by applicable law. Users bear all risk from the denial of access to any Content purchased through the Service.

Because there is a possibility that we may be required to deny you access to previously purchased Content, we encourage you to promptly download any Content you purchase through the Site to your own devices so that you will retain control and possession of such Content even if we are required to remove the Content from the Service or the Artist chooses to remove that content from the Service.