The old kernels should actually be autoremoved and that not happening is being tracked in the following bug:
https://bugs.launchpad.net/ubuntu/+source/update-manager/+bug/1439769
The old kernels should actually be autoremoved and that not happening is being tracked in the following bug:
https:/ /bugs.launchpad .net/ubuntu/ +source/ update- manager/ +bug/1439769