"...provide updates for max 24 months..."
My decade-old car is constantly having its software updated. The dealer plugs in his laptop during every Full Service, and leaves it connected for the duration. I've noticed that the Speed Limiter often seems to have a different setting after some Full Services. I've seen limits at 250 (well, 235+), 220, and 210 (very disappointing) kmh. I've also noticed other details changing, seemingly related to system software.
Perhaps duration of support depends on the manufacturer.