BA has launched a sale for selected destinations in Europe in Club Europe. Book by 17 May.
There seemed to be decent availability when I checked to a number of destinations.
The new service from London City to Berlin was included when I checked.
In addition you can cash in some Avios to get the price even cheaper prices.
Presumably these are all ex-LON only, ignoring connections from the regions as per usual with BA? 🙁