I have been watching the same site this year and have seen all the nuptial behaviour which I described last year. From late May until recently there has been an adult sitting at the site, incubating the egg. Fulmars lay only one egg per year and incubation is a lengthy process: about 50 days. It is impossible to look down into the nest site so I have not seen the egg, but the behaviour of the birds made it easy to deduce that there was an egg being incubated. This morning I could see a chick in the "nest" (Fulmars do not build a nest as such: it's essentially just bare rock, although I have observed the adults "housekeeping": moving bits of debris and throwing them out.).
An adult at the nest site, incubating in June this year
The chick in the same place, today, July 30
A closer view of the chick
This is progress compared to last year and I do hope that this young bird will make it. It will probably fledge at the end of August or beginning of September (the fledging period is around 46-51 days). It is therefore essential that there is no climbing on Lewes Castle until September. Anyone who does climb there before then will probably kill this bird.