This issue is due to a large volume of non compliant roofing battens entering the UK market.

This is thought to be due to the high demand for treated timber, which was compounded by the shortages created by conflict in Ukraine, Brexit and the pandemic. The battens have been falsely stamped with BS 5334 and/or falsely coloured, and then marketed as compliant.
View the full article here.

Non-compliant battens should not be installed: they have the potential to cause roof failures and serious accidents.

The NFRC's article clearly states how to identify compliant battens.

Rest assured, roofing batten purchased from any of our branches is not affected, and is fully certified.