After installing a 3rd kernel currently 3.19.0-12-generic, the /etc/apt/apt.conf.d/01autoremove-kernels file looks normal listing the 3.19.0-11-generic and 3.19.0-12-generic with 3.19.0-10-generic listed to be autoremoved. But once autoremove is completed the machine requests to be rebooted and at that time the /etc/apt/apt.conf.d/01autoremove-kernels file lists the 3.19.0-12-generic and 3.19.0-10-generic kernels. So upon rebooting the 3.19.0-11-generic is requested to be autoremoved leaving only one kernel the latest one 3.19.0-12-generic.
ProblemType: Bug
DistroRelease: Ubuntu 15.04
Package: apt 1.0.9.7ubuntu3
ProcVersionSignature: Ubuntu 3.19.0-12.12-generic 3.19.3
Uname: Linux 3.19.0-12-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.17-0ubuntu1
Architecture: amd64
CurrentDesktop: MATE
Date: Sun Apr 5 17:03:01 2015
InstallationDate: Installed on 2015-04-02 (3 days ago)
InstallationMedia: Ubuntu-MATE 15.04 "Vivid Vervet" - Beta amd64 (20150401)
SourcePackage: apt
UpgradeStatus: No upgrade log present (probably fresh install)
After rebooting and autoremoving the 2nd oldest kernel the /etc/apt/ apt.conf. d/01autoremove- kernels file reverts to listing the 3.19.0-11-generic and 3.19.0-12-generic kernels. So only one kernel, the latest 3.19.0-12-generic is left.