Here's how that can make sense in a closed-primary state such as Florida. Those self-identifying "independents" registered as Republicans 30 days or more ahead of the primary. For that matter, Democrats could change their party affiliation to Republican as well, as long as it was done 30 or more days ahead. Now they can either go back to being registered RATS or drop their party affiliation.
I believe that was part of the strategy once it was clear that Florida's RAT delegates wouldn't be seated to cross over to select the weakest republican. That had to be done back in December and when Hillary suddenly wanted to put the state in play, it was too late to switch back to get a RAT ballot and vote for Obama or the Silky Pony.