That a two-tier licensing system is being used under current legislation, I could see the potential for voiding existing licenses in the event of a change to legislation. However, this might pave the way for system manufacturers to reclaim license fees.
Before looking at variables, I'd sooner wait for the ruling then look at potential options/impact.
The contract aspect is of more interest to me, for the intent of both parties when licensing. If it can be shown(please note the MMP Portfolio disclaimer by those manufacturers who have licensed, which basically says, Just because we are a licensee doesn't mean you don't have to license as well)that a discount/certain price was given so that other users would still be liable, then there will be many lawyers burnig the midnight oil.
There are many interesting scenarios.
Be well