Inconsistent hand baggage sizes on Flybe website

Flybe's Baggage FAQ states that hand baggage on its non-Loganair flights must not exceed the dimensions 55cm x 40cm x 23cm and a weight restriction of 10kg.

The online check-in form states contradictory dimensions, suggesting a significantly smaller 50cm x 35cm x 23cm.

Which is it?!

Flybe's baggage policy is already much less generous than many other airlines: for example easyJet allow 56cm x 45cm x 25cm with no weight restriction as long as you can lift it.