Only some % of responses will be those switching parties. A good proportion will be from party x to Don't Know/Won't Say.
Analysis by pollsters shows a not insignificant part Reform's vote come from previous non-voters.
Sankey diagrams help explain what's going on.

The decline in party membership since 1948

In which people learn the hard way why voting Labour is the optimal choice given the complexities of modern times

The shocking state of political discourse amongst the general public

The past is a foreign country…
www.bbc.co.uk/blogs/radiol...

The Awesomeness of Donald Trump www.theneweuropean.co.uk/podcast/the-... @thetwomatts.bsky.social

When someone comes to write the book of how the Conservative Party became so adrift from reality this will be amongst the artefacts held up for bewilderment

@snowded.bsky.social announces his departure from toXic