Evektor Ltd. has issued the mandatory safety alert bulletin no. Harmony LSA-019a SR as unification of the strength class of the fastening bolts (bolts M10x35 of original strength class 8.8 are changed to strength class 10.9) in the joint of the engine and the engine mount hinges and the resulting minimization of the possibility that these bolts will be accidentally interchanged. In relation to SB LSA-019a SR, the manufacturer requires repetitive visual inspections of each engine attachment points to suspension frame/engine mount, suspension frame/engine mount and engine mount to aircraft firewall attachment.