can't upgrade from kubuntu 15.10 to 16.04

[Barmaglod]

when "sudo do-release-upgrade -d" or "sudo do-release-upgrade"

then:
"Не удалось рассчитать обновление системы

Обнаружена неразрешимая проблема при расчёте обновления.
"

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: ubuntu-release-upgrader-core 1:15.10.14.4
ProcVersionSignature: Ubuntu 4.2.0-36.41-generic 4.2.8-ckt8
Uname: Linux 4.2.0-36-generic i686
ApportVersion: 2.19.1-0ubuntu5
Architecture: i386
CrashDB: ubuntu
CurrentDesktop: KDE
Date: Fri Apr 22 08:53:46 2016
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to wily on 2016-04-22 (0 days ago)

[Brian Murray (brian-murray)]

Reviewing the files from your upgrade attempt you seem to have enabled a PPA that provides Xorg packages. This will prevent the upgrade as that PPA contains different versions of packages essential to Ubuntu. The page, https://launchpad.net/~xorg-edgers/+archive/ppa, contains details on to how to revert to the official Xorg packages for the xorg-edgers PPA. Instructions for reverting to official Xorg packages should be similar for the PPA that you have enabled.