With less than three weeks before a looming deadline for enrolling in mandatory health coverage, the federal government has unveiled several rule changes affecting Obamacare insurers and their customers.
The changes, revealed in a flurry of announcements in recent days, will broaden the size of provider networks in some health plans next year, give insurers financial relief, affirm that certain groups will receive health benefits that were being questioned and extends temporary coverage to some people with pre-existing conditions.
Amid those announcements, The Wall Street Journal reported late Friday that officials are preparing to effectively grant an extension of the March 31 deadline for Obamacare enrollment to last-minute shoppers who run into technical problems on government exchanges, and who can document those problems.
Federal officials Monday said only, "Open enrollment ends March 31," when CNBC.com asked about the Journal report.
But if officials do end up extending the deadline, it would not be surprising. In December, when dealing with large numbers of people trying to sign up for health coverage beginning Jan. 1, 2014, the government several times effectively extended the enrollment deadline, and leaned on insurers to get them to honor sign-ups that occurred after the deadline.
(Read more: All over the map: States' 'paid' Obamacare rates )
Under the Affordable Care Act, nearly every American must have some form of health insurance by March 31 or face a tax penalty next year.
One major change announced by the government will effectively compel insurers selling plans on the Obamacare exchanges for 2015 to increase the minimum number of so-called essential community providers in the plans' networks. Such providers serve lower-income and other "medically under-served" populations, and include federally qualified health centers, children's hospitals, HIV and STD clinics, and family planning clinics.
Under the rule change, plans that include "at least 30 percent of available essential community providers" will be considered for listing on an Obamacare exchange next year. That is an increase from at least 20 percent for plans being sold this year. Insurers that don't meet the new 30 percent minimum will have to explain how their network gives customers adequate service.
The rule change is being made in response to complaints that some Obamacare plans were too limited in the providers they offered enrollees.
But the industry lobbying group America's Health Insurance Plans, in a Feb. 25 letter to the Centers for Medicare and Medicaid Services, had cited its "great concern" that CMS would consider making that change and others, to 2015 plans. AHIP noted the deadlines for plans to apply for approval for their 2015 plans and rates "is just months away."
"Only when a fully functioning, stable system is achieved do we believe it is time for CMS to propose such adjustments to the program," AHIP's executive vice president for policy and regulatory affairs, Dan Durham, wrote.
More for insurers
While insurers are not apt to be happy about that rule change, they likely will be pleased with proposals that will keep more money in some of their pockets.
(Read more: House GOP: How many have paid for Obamacare? )
One such proposal relates to the amount of administrative costs that insurers are allowed to claim under a program that requires them to give rebates to customers if they fail to spend a certain percentage of premium payments on health benefits.
Benefits for same-sex partners
In a win for proponents of same-sex marriage, the government last week also told insurers that if they sell family health coverage plans to people in traditional marriages, they must also sell such plans to same-sex couples who were married in one of the 17 states or the District of Columbia that allow such marriages. That rule prevails regardless of whether the couple now lives in a jurisdiction where same-sex marriage is not legal.
The government also finally put to bed an odd, simmering controversy over whether insurers selling Obamacare plans on government-run exchanges could accept payments for premiums for customers from Ryan White/AIDS programs, which provide financial help to people suffering from HIV and AIDS.
The government told insurers they must accept such money; some insurers had previously refused the funds on the purported grounds that they violated anti-kickback laws, which bar hospitals and other health-care providers from paying someones' premiums.
(Read more: Who are these people? Insurers scope out new enrollees )
Another rule change gives people who currently have health coverage through the federal high-risk pool until April 30 to find a replacement plan. The prior deadline had been March 31.
The "Pre-existing Condition Insurance Plan" was established to give coverage to people who could not obtain private insurance before Obamacare because they suffered from a pre-existing condition. But new ACA rules bar such discrimination by insurers.
—By CNBC's Dan Mangan. Follow him on Twitter @_DanMangan.