Does Xubuntu 18.04 have support only 3 years while Ubuntu 18.04 has 10 years?

Question

I just saw that Xubuntu 18.04 will have LTS support only until 2021 while the standard Ubuntu 18.04 will have LTS support until 2028.

Is this correct? Aren't the updates for Xubuntu and Ubuntu coming from the same repositories? Will some updates from the standard Ubuntu still be installed for Xubuntu after 2021? If so, which updates will be installed and which not?

Edit 1: Adding Sources

1. Support for Xubuntu until 2021 Xubuntu Website

2. Support for Ubuntu 18.04 extended to 10 years.

Linux.Org Forum

ServerWatch

Edit 2: Comment by @pomsky solved the question. Only unclear point is: Since Ubuntu 18.04 might be the first version to have LTS = 10 years, wouldn't it make sense that other flavors will also have extended LTS?

Also regarding which updates will still be available and which not, the two other questions posted by pomsky provide the answers: Anything related to the desktop environment, packages that come only from Xubuntu will not receive any updates after the LTS for Xubuntu ends. But the core aspects, the system related packages will still receive updates because of the Ubuntu LTS.

Answer 1

• Canonical, the company behind Ubuntu, provides 5 years of support for LTS releases of Ubuntu Desktop and Ubuntu Server. There are indications, that the support for LTS releases will be increased to 10 years.

• Each team behind the Ubuntu community flavours, Kubuntu, Lubuntu, ... Xubuntu, decides the length of support, and now most of them provide 3 years of support for LTS releases. These teams consist of volunteers, and have limited resources, that must be shared between development of new versions and support of released versions.

• All current non-LTS versions are supported for only 9 months.

• You are welcome to participate in the development, maintenance and testing of Ubuntu and the Ubuntu community flavours.