Did Eastbourne's beach suffer due to the defending of another beach along the coast?

Question

Didn't the building of sea defences in another beach in another place make Eastbourne suffer (whether it was the loss of shingle or long-shore drift was different)? And the creation of sea defences in Eastbourne means Hastings (I think) has to suffer the consequences.. But where was the place that put Eastbourne in that position?

Answer 1

Any defences West of Eastbourne, that prevent the natural movement of beach deposits in an Easterly direction, affect coastal errosion at Eastbourne.