As Republicans in Congress debate changes to the Affordable Care Act, insurance executives across the country are trying to make plans for next year.

Companies that sell policies on the exchanges created by the Affordable Care Act, also known as Obamacare, face fast-approaching deadlines to inform states about what plans they want to sell, and what they intend to charge.

"Insurance companies need to file rates in 2 1/2 months," says Tom Policelli, CEO of Minuteman Health, which sells Obamacare policies in Massachusetts and New Hampshire.

"So basically we've got four to six weeks to figure out some basic things that will help all of us in the industry to have more surety and stability, so we can price our premiums lower," he says.

To make those decisions, companies want to know whether the law is going to change altogether, something Republicans in the House have tried, failed to do and are trying again this week.

At minimum, insurers would like to know whether the Trump administration intends to continue making crucial payments to insurers that are required under the law.

On Wednesday the president seemed to agree to continue those payments, known as cost-sharing subsidies, but Thursday he tweetedthat he would not "give billions to insurance companies."

"The current debate is largely not helpful, and is heading things in a direction that will make things even worse," Policelli says.

The payments reimburse insurance companies for discounts they are required to give to low-income customers to offset deductibles and co-payments.

Without the subsidies, a study by the Kaiser Family Foundation shows, premiums could go up 19 percent. And ending the the subsidies could also cost the government as much as $2.3 billion in 2018, according to Kaiser, because the government would need to offset those premium increases.

Policelli says the markets have lots of other problems too. It's technical stuff, he says, such as medical loss ratios and risk adjustment schemes.

"This sounds very boring. It is very boring. I'm an insurance guy, I'm very boring," he concedes. "But this stuff is killing the industry and driving out competition and driving prices up."

He says lawmakers could fix the problems if they want to. And if they don't, Trump could do a lot on his own, through regulation.

It's not clear that the president, who has repeatedly threatened to let Obamacare "explode," wants to make the current system work better. And Congress continues to debate changes in the law that would go into effect before next year.

So Policelli is preparing for 2018 without knowing what rules he'll have to play by.

"At times it feels like you're building a boat, while at sea, in a storm, at night. But that's what we're here to do," he says.

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