Here's the reality. UC doesn't have to follow at-will law
Yes, it does. That is the whole and entire point regarding that entitlement.
Show me the court decision that states it has to. Don't just post another meaningless quote from a law that you pretend makes the case, cite the actual court decision. And naturally, you'll have to then strike down all means testing everywhere in all entitlements to be valid. That means Social Security can no longer be restricted to seniors, Medicare to seniors and the disabled, Medicaid, food stamps and section 8 housing to low-income earners. Disability has to be paid to the non-disabled, and so on.
You dug the hole, now you need to admit it because it's too deep to get out of.