Hilary Benn at People's Vote rally in Leeds

The transcript discusses the democratic process, highlighting Theresa May's repeated returns to Parliament to check if MPs had changed their minds. It argues that it is equally democratic to ask the British public if they have changed their minds. The speaker calls for political parties to clearly express their positions.

In what context does the speaker mention changing minds?

What does the speaker mean by saying 'let the party that I joined when I was 17 years of age say it loud and clear'?