Ongoing version support?

I  bought a Dell XPS 13 9360 last year and it came with Ubuntu 16.04. October came and went and there was no sign of an official Dell 16.10 upgrade that I could see. Now 17.04 has been released and I see no word of an official Dell release yet. I understand it may take a while to get it ready after the Canonical release. And maybe you only plan to support the *.04 releases. I'd just like to know what I can expect.

I've tried other distros with the machine, even vanilla Ubuntu 16.04 and had lots of problems, particularly with sound. So I'm kind of stuck with what Dell provides, unfortunately. Thus, I'd love to know what will be provided going forward. I know Ubuntu is planning some big changes in 18.04 - dropping Unity and replacing it with Gnome. I paid a good amount for this computer and plan on having it at least that long. I'd hate to be stuck on a 2 year old release because Dell gave up on updating it.

An even better solution would be to provide the custom drivers, etc. that make the Dell image work, so that I could install whatever distro I want and still be able to get the sound card to work. One of the main benefits of using an open source OS like Linux is choice. I'm disappointed that I cannot install another distro, and am stuck with a Dell version of one particular release of one particular distro.