Sometimes casework is small and specific - in this case, the metal bracket for the Pilsden Place sign has rusted through and the sign is about to drop off. I've asked for a replacement to be ordered - these are done in large batches, so hopefully we'll see a replacement before not too long.
UPDATE - I've also been asked to order a replacement sign for Kestrel Avenue, as the sign at the junction with Farnborough Drive vanished some years ago and has not been replaced.
