I agree that they need to wrestle back some control. The key may...

I agree that they need to wrestle back some control. The key may lie with the new licenses. If they win these, then the prospect of utilizing the infrastructure from phase 1/2/3 will be invaluable to those licenses, given their proximity to the existing project.
I think HHR still have a number of options. Here are my three but I’m sure there maybe more: 1) hold out and see if RR go to FID (most likely) 2) sell the remaining 20% to RR and keep any new license for a rinse and repeat (less likely now) and 3) merge with another producer that generates income and needs future projects (some of the current smaller producers have lots of cash and very low EV’s).
Regards the possible change in govt and therefore a change in fiscal terms, I tend to agree with @Hotfire . Labour would be incredibly stupid to force the closure of future production with idealistic policy. They have a rich history of talking out of both sides of their mouth