We’re using Blockstack.js (latest version) to initiate Blockstack auth requests from the front-end then are using the back-end library to process the authentication requests server-side using this library (https://pypi.python.org/pypi/django-blockstack-auth)
This authentication flow works fine, until a browser session has been open for a long time (overnight), at which point the authentication requests that are made through the Blockstack browser no longer return the expected payload and the auth request fails.
Re-starting the browser (google chrome) seems to solve the issue. Have been testing on the Mac Browser client across different devices and the same issue pops up.