In my younger electioneering days, we used to quote a, no doubt, apocryphal, Irish saying 'vote early, vote often'.
But on the mainland, as far as I know, the problem, and that fairly small, is with postal votes.
Perhaps it was introduced to bring us in alignment with other countries. Possibly the relevant authorities know something we do not know.
I was surprised to see one of the papers suggesting that it disadvantaged older people. I am sure some were, but most older people have driving licences, passports, bus passes or other identification, so I wouldn't think the numbers having problems were any higher than in any other age-group.
Just another case of casual institutionalised agism.