Corona 60w filament lamp made in the UK

Here is another unusual lamp which was kindly given to me by another collector, branded "Corona" (mind you, nothing to do with the Spanish "Corona" company). Going by the etch, I'm not entirely sure who made this lamp - it's a bit of a mystery! The presence of a Philips date code could imply that it was made by them. This lamp has a single coil/wreath filament.