Why is there no long-term supported Yocto version (Dunfell e.g.) for digi?

For IoT application e.g. with ConnectCore 6UL it would be appreciated, if there are long-term support versions of Yocto to build the platform.
Dunfell would be great, it exists since 2020 and will be supported by Yocto until 2024. However, Digi has no branch Dunfell in its digi-embedded repository.

Only Gatesgarth is available at digi, which however has already reached end-of-life (May 2021).

TIA
Wolfram

We are working on Kirkstone (4.0) whci is also long term support one.

https://www.digi.com/resources/documentation/digidocs/embedded/dey/4.0/cc6ul/index

Digi Embedded Yocto DEY-4.0 is available since 2022