It seems a firmware update for the Hue bridge and Hue bridge 2 has removed compatibility to 3rd party lamps, that version of the firmware will only work with “Friends of Hue” lamps and no longer support generic Zigbee Light Link lamps.
There was a lot of backlash on this as it can make existing, working, setups useless and raised questions about Philips still effectively being a member of the TCLA and if Hue bridges are still Zigbee complaint ?
One sore point seems to remain : Apple HomeKit certification apparently not only applies to the Hue bridge but also to the lamps connected to the Hue Bridge :
Before the 1.11 software update, a bug in the Philips Hue system allowed some non-Apple HomeKit certified lights to work with Apple HomeKit. Our 1.11 software update removed the bug with the result that non-Apple HomeKit certified lights no longer work with Apple HomeKit. This remains the case.
The discovery and confirmation of the update that removed support :
iPhone-Ticker : http://www.iphone-ticker.de/firmware-update-fuer-philips-hue-verhindert-das-einbinden-von-osram-lightify-90450/
Meethue on Twitter : https://twitter.com/tweethue/status/674248181425774592
The announcement of the reversal :
Meethue : http://www2.meethue.com/en-us/update
Twitter : https://twitter.com/tweethue/status/677597933638955008