UK politics is moving at speed, with voter loyalties shifting and atomising in unprecedented ways.
If anyone inside No 10 allowed themselves a sigh of relief at Reform UK's advance being stymied in the Caerphilly byelection, they would then have heard the warning from Lindsay Whittle, Plaid Cymru's winning candidate:
“You are on your way out after 100-plus years.”
Lindsay Whittle argued that Labour in Wales might be "a dying beast", and this one-off Senedd race illustrated how it was on course to lose its grip on Welsh politics in May, with potentially wider implications for Keir Starmer and his party.
Author's summary: Labour's by-election loss in Wales shows parties must adapt to survive.