Post
I feel that since the postal votes also need to be posted back, a guarantee only that they'll arrive before polling day isn't really good enough. 'we remain confident that...' is management speak for we don't want to scare the horses, but there's a real risk here... Just slap a legal obligation on them to deliver ballots (and 1st class) within 48 hours of being posted anywhere within UK. "I haven't asked for detailed numbers, so I'm not actually lying."