On the erroneous notion that in mid-January the U.S. will end its policy of admitting for residence those Cubans who reach its shores, growing numbers of people have been fleeing the island in hopes of beating the deadline.

Since Dec. 17, more than 400 Cubans were encountered trying to head to the United States, mainly through the Florida Straits, according to the U.S. Coast Guard. That is about three times the number that attempts to reach the United States each month.

Dec. 17 is when President Barack Obama announced that the U.S. was restoring diplomatic relations with Cuba, ending a thaw of more than 50 years.

U.S. authorities have captured, intercepted or chased away 421 Cubans since Dec. 17, mostly in the Florida Straits, said Lt. Cmdr. Gabe Somma, spokesman for the Coast Guard's 7th District in Miami.

In all of December 2013, the total number of Cuban migrants who encountered U.S. law enforcement while trying to reach the U.S was just 222.

And just before the historic announcement of the U.S-Cuba detente — from Dec. 1 to Dec. 16 — only 132 Cubans were kept from reaching U.S. shores.

Some Cubans recently told The Associated Press that they were thinking about speeding up their plans to get to the U.S., but others cautioned against attempting the dangerous crossing when it's still unclear how U.S. law may change.

"I'm crazy to leave, but I'm not going to throw myself into the sea, I'm not going to do it," Juan Moreno, 34, said in Havana on Monday. "He who does that is crazy."

The Coast Guard says the significant increase in the number of Cuban migrants has been prompted by rumors that an abrupt end is coming as soon as Jan. 15 to the so-called wet foot-dry foot policy that usually shields Cubans from deportation if they reach U.S. shores.

But U.S. officials say there are no immediate plans to change the policy. Congress would have to change the Cuban Adjustment Act or the U.S. trade embargo.

"There is no change to immigration law. This rumor is just putting people in harm's way. The rumors are just not true," Somma said.

The overall number of migrants making risky sea voyages toward U.S. shores from the Caribbean, including Cuba and other countries, has spiked in the past year. 

According to the Coast Guard, in the fiscal year that ended Sept. 30, U.S. authorities captured, intercepted or chased away at least 5,585 Haitians, 3,940 Cubans and hundreds from the Dominican Republic and other Caribbean countries attempting to sneak into the country.

For nearly 50 years, Cubans have had a unique privilege. The Cuban Adjustment Act has given them a virtually guaranteed path to legal residency and eventual citizenship. 

Over the years, hundreds of thousands of Cubans have taken perilous raft trips to Florida and land journeys through Central America and Mexico with the knowledge that they would not be deported.

Cubans caught at sea, though, usually are returned home.

Coast Guard officials stopped short of calling the recent surge a mass migration, but they said they're concerned about the increased numbers of migrants.

"At one point last week, we had about 120 Cuban migrants on Coast Guard cutter decks awaiting repatriation," Somma said.

Some Coast Guard vessels and aircraft have been pulled from other missions in the region to address the increased migrant traffic in the waters off Florida, Somma said.

Poverty and political repression have long caused Cubans and other Caribbean islanders to attempt the journey across the swift currents of the Florida Straits, and a recovering U.S. economy and another calm summer without many tropical storms may have contributed to the increased flow of migrants documented since the federal fiscal year that began Oct. 1, 2013.

But now that the U.S. and Cuba are negotiating a return to full diplomatic relations, many Cubans wonder how long wet foot-dry foot will continue.

Moreno and others in Cuba said that they expected the changes announced last month to take time, and that the Cuban Adjustment Act would eventually go away, whether or not circumstances on the island improved.

"The truth is that someday it will be removed, but it's unknown when," Moreno said.

 Based on reporting by The Associated Press.

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