Last year I wrote a LOT about Silver Loading and Silver Switching for 2018...basically, the way which ACA individual market enrollees can save hundreds or even thousands of dollars on their 2018 insurance policies by taking advantage--perfectly legally and ethically--of the unusual pricing of different metal level policies this year.
The short version is this: Due to the way the ACA's tax credit formula works, Donald Trump's attempt at sabotaging the ACA exchanges by cutting off Cost Sharing Reduction (CSR) reimbursement payments to insurance carriers actually (partly) backfired on him, resulting in an unusual situation in which several million subsidized enrollees ended up benefitting from the pricing fallout, while millions of unsubsidized enrollees ended up being hurt by it...but other unsubsidized enrollees ended up being able to avoid being hurt by switching to a special off-exchange Silver plan (thus, the "Silver Switch").