Team Trump knows exactly how politically dangerous their request that the courts invalidate the Affordable Care Act is, so they've come up with some pretty obnoxious ways to try to avoid the consequences in 2020. They are currently preparing to ask a federal appeals court for a stay if the court rules Trump's way, and "may try to delay a potential Supreme Court hearing on the matter until after the 2020 presidential election, according to current and former administration officials."
They also say the "have some ideas for replacing parts" of the law. They don't. Particularly for the parts that are most far-reaching, like the benefits of 133 million people with pre-existing conditions or the coverage about 20 million previously uninsured people have secured. However the Fifth Circuit Court of Appeals—a notoriously conservative activist court—rules, the Department of Justice will try to delay the outcome. They'll ask for a stay if the court rules for them and will delay an appeal to the Supreme Court if it rules against them. Anything to make sure that any final decision doesn't come down before the 2020 election.
This isn't even the most cynical move William Barr's Justice Department has made on the ACA, though. They've actually filed a bizarre letter with the Fifth Circuit arguing that the court could invalidate the law only in the Republican states that brought the suit. Yes, the Department of Justice is arguing that the national law is totally unconstitutional but if the court strikes it down, it should only strike it down in the states who will still vote Republican. Which is not at all how law works, but the Attorney General of the United States signed off on it.
It's also completely unworkable. Take just the example of the requirements for coverage of preventive care and prohibition of annual and lifetime benefit caps. These reform apply to all insurance, including employer provided insurance. How does a national company with employees in multiple states deal with that? The Employee Retirement and Income Security Act (ERISA), the federal law regulating employer-provided health benefits is based on the principle that there can be no state-to-state variations in the law that governs employer's health benefits. So this argument by the Barr and team would contradict another standing law.
The administration's ridiculous contortions on this shows a number of things. They know Trump's and the GOP's shrinking base is still going to demand the obliteration of Obamacare so they're trying to keep the issue alive. But they know that total repeal is going to destroy them politically, that it will drive an angry tsunami of people to the polls in November 2020 and bury them. It also demonstrates just how confident they are that the Supreme Court is now Trump's. They expect it to destroy the law, they just want it to wait until it's less politically inconvenient.