It's not just Turbomeca engines, P&WC and R-R have their own preservation requirements too, and not too dissimilar if I remember right. Piston engines are also included, Lycoming have MM requirements and a Service Letter on the subject (confusingly the Lycoming MM and the SL say different things).
It's nothing new, it's been in the MM's for a long time, it may be overlooked by operators but it's certainly a hot topic with the regulators.