Quartus Prime (Pro) - Ubuntu 18.04 and pricing ...?

Hello, Intel Customer Support suggested I pose my queries here, noting that a(n Intel?) representative dedicated to the product (Quartus Prime) would attend to them.

I'm considering development on the Arria or Stratix 10 FPGAs, however I have two questions regarding the Quartus Prime (Pro) software and would appreciate Intel's assistance.

1. The system requirements do not include Ubuntu 18.04 LTS, even though it has superseded 16.04 (and 14.04). Does this mean 18.04 is not (yet) supported?
2. The licence for Quartus Prime (Pro) is $US 3,995. Is this an annual thing or a 'one off'? Descriptions on parts of the site regarding 'subscriptions' seem to infer an annual renewal fee of over $US 3,000 (but I could be wrong), whereas other areas imply this is a 'perpetual' licence. I'd like to understand what I'm up for in using the pro version for a number of years.

I'd be extremely grateful for clarification on the above.

Regards,

Paul Menon