This old Eurotunnel advert always amazes me.

🚫 A Vacancy doesn't always mean a by-election! Did you know that by-elections are virtually unknown in Northern Ireland? Or that the recent Senedd reforms have abolished them entirely for the Welsh Parliament?

In other words, what's happening now is unprecedented in universal franchise Westminster elections. First past the post breaks down entirely in these circumstances. Voters already know this - support for reform to the Westminster electoral system is higher now than it has ever been before