Migrants have been flown from the Rio Grande Valley in Texas to San Diego for processing. Plans indicated at three flights per week with ~130 migrants or ~400 or so overall. There has also been some busing more locally to Laredo or to El Centro.

Stated reason is because of processing deadlines (20 days) and increased influx of children.

Migrant families being flown to San Diego from Texas in U.S. border crisis

Hundreds of detainees from U.S. Customs and Border Protection (CBP) facilities in Texas and elsewhere are being flown to San Diego for processing beginning on Friday, the agency said.

Reuters

For example this story of migrants released in San Luis

Central American Migrants Released in San Luis

Thousands of Central American migrants who are seeking asylum have been released in Yuma for weeks and now some are being released in San Luis.A sign was…

KAWC

As far as numbers go, if there are 4,500 migrants apprehended per day then sending 400 per week on planes and some more per buses isn’t a huge proportion. So expect there is also some political motive to generate stories like this one to fan flames of concern

Trump administration prepares to release Central American migrants 'across the entire nation'

With more than 4,500 people being caught each day crossing the U.S.-Mexico border, the agency has run out of room in the four border states.

USA TODAY

This lets it be a local story in Florida that the senator can comment upon

Rubio: Border Patrol to Transport 500 Migrants a Month from Border to Florida

Sen. Marco Rubio, R-Fla., said Thursday that U.S. Border Patrol will start moving 500 migrants per month to two counties in Florida beginning next week and "releasing them pending an asylum hearing."

Newsmax

Still recall similar (but larger scale) political effects from Cuban refugees detained in Fort Chaffee Arkansas. Spread some asylum seekers out and increase the odds of some incident.

1980 - Crisis at Ft. Chaffee - Arkansas Times

Overcrowding and frustration lead to riots by Cuban detainees, and a national spotlight on Arkansas.

Arkansas Times