TALLAHASSEE, Fla. (AP) — Florida regulators are warning that a preliminary report estimating a new law will cut no-fault auto insurance premiums by 12 percent to 20 percent may be misleading and overly optimistic.

The Office of Insurance Regulation released a consulting firm's draft report Friday in response to public records requests by the news media. The final version is due Sept. 15. It's required as part of the new law, which is designed to reduce insurance fraud.

"The final conclusions may, and probably will, change prior to the report being finalized," wrote office spokesman Jack McDermott, who also issued a list of caveats.

One is that the estimate is for premiums that insurers are entitled to receive. Companies, though, often ask for lower premiums because auto insurance is highly competitive. That difference could reduce or eliminate any savings.

Another caveat is that the savings would be just for personal injury protection, or PIP, which accounts for only about 20 percent of a typical insurance bill.

Also, any savings will not be realized until Jan. 1, 2013, at the earliest and there's no requirement for insurers to accept the report's findings.

Insurance companies, meanwhile, could seek premium increases for other reasons that could negate all or part of any savings.

Donovan Brown, state governmental relations counsel for the Property Casualty Insurers Association of America, also urged caution on the draft report prepared by Pinnacle Actuarial Resources Inc.

Brown noted that the law will not be fully implemented until next year and courts may interpret it differently than the Legislature intended.

It calls for a 10 percent premium savings unless companies can explain why they can't cut that much. Insurers also are required to cut rates by 25 percent in a second rate filing due Jan. 1, 2014, but they again can avoid it with an explanation.

Florida motorists have been required to buy no-fault PIP coverage since 1972 to make sure anyone injured in a crash gets money to treat their injuries without delay. A driver's insurance company is required to pay up to $10,000 for medical bills and lost wages no matter who is at fault.

Bogus claims and faked accidents, though, are largely responsible for a $1.4 billion increase in PIP costs since 2008, state officials say.

The new law puts a 14-day limit on seeking treatment after a crash. Benefits also are capped at $2,500 unless a doctor, osteopathic physician, dentist or a supervised physician's assistant or advanced registered nurse practitioner determines there's an "emergency medical condition." Chiropractors cannot make that determination.