We're experiencing this issue - "Install Managed Package Into Sandbox Fails on All Lightning Component Bundles" that is affecting other vendors as well, where our package with new Lightning components cannot be installed into sandbox environments. Prod environments work fine.
This error has happened with a few older Salesforce releases, and got fixed, but it's likely to be a matter of days or more before that happens.
In the meantime, anyone got a workaround that allows us to deploy new Lightning components to customer sandboxes? We have one customer who desperately needs our new components and can't accept them right now.