Looks like they - quietly - removed their lowest fare category across all routes. Gone are the 'VLM Promo' fares, the cheapest offer is now the 'VLM Essential' tariff. Comes down mostly to a small to rather substantial price hike, depending on the route:
(All fares O/W)
Antwerp - Southampton: 49 Euro -> 54 Euro
Hamburg - Southampton: 126 Euro -> 65 Euro (yes, going down)
Waterford - Birmingham: 49 Euro -> 81 Euro
Waterford - London Luton: 49 Euro -> 83 Euro
Antwerp - Hamburg: 48 Euro -> 63 Euro
Rotterdam - Hamburg: 58 Euro -> 64 Euro
Antwerp - Geneva: 39 Euro -> 55 Euro