No; before the item is baked, the design can simply be wiped off with a damp cloth, so it's still possible to make corrections.

The edding 4200 porcelain brush pen is designed for decorating on porcelain, glazed ceramics and ovenproof glass. To set your decoration when it's finished, you need to bake it in a conventional oven at 160°C for 25 minutes. Only then will it be able to withstand the dishwashing process.