Okay, here's a voting anecdote from the 2016 primary election.
This year's vote includes the goofy populists Donald Trump and Bernie Sanders. Trump claims to have appeal to Democrats. Sanders claims to have appeal to Republicans.
I've heard talk about Democrats voting Republican to help set up a Trump vs. Democrat national election final that favors the Democrat. I'm not aware of any solid evidence supporting this type of charge. But my anecdote may relate.
Upon arriving at my precinct, I saw a woman coming out of the precinct complaining that "someone" changed her party. She appeared irate, and I inferred that the the change in registration affected her ability to vote for her favored candidate.
An election worker asked the woman to what party she had been switched. For the sake of my own curiosity I wish she had answered the question, but she did not.
Upon getting in line to have my photo ID and signature matched, I overheard a woman ahead of me in line request a change in her party registration. To me it sounded like the election worker described a way the woman could change her party and vote in the primary. But according to this article the deadline for changing parties was Feb. 16, 2016.
It's certainly possible that I received the wrong impression about what the woman was told about changing her party. I would not allege any impropriety based on my impression of what I heard.
What does it all mean?
Maybe nothing. While I don't recall ever hearing anything at the polling station about changing party affiliations, perhaps I was keyed to pay more attention to the issue because of the reports I have heard. Or maybe changing parties was discussed in my presence in the past and I just don't remember it.