К сожалению, бюллетень, на который там идет ссылка (SB A320-53-1266)
Там вот о чем:
During the A320 fatigue test campaign for Extended Service Goal (ESG), it was determined that fatigue damage could appear on the clips, shear webs and angles at rear fuselage section 19, on Frame (FR) 72 and FR74.
This condition, if not detected and corrected, could affect the structural integrity of the aeroplane.
To address this potential unsafe condition, Airbus developed a modification, which has been published through Airbus Service Bulletin (SB) A320–53–1266 for in-service application to allow aeroplanes to operate up to the new ESG limit.
For the reasons described above, this [EASA] AD requires replacement of the affected clips, shear webs and angles at rear fuselage section 19, FR72 and FR74 [including all applicable related investigative actions and repair if any cracking is found].
Airbus has issued Service Bulletin A320–53–1266, Revision 01, dated June 20, 2013. This service information describes procedures for replacing clips, shear webs, and angles at rear fuselage section 19, FR72 and FR74. The actions described in this service information are intended to correct the unsafe condition identified in the MCAI.