A Line Mechanic reports about a new and confusing sign-off process in their Procedures Manual (P/M) that does not allow a Mechanic; assigned a Periodic Service (P/S) Check Card; to sign-off multiple sequential tasks with the reference 'Previously Accomplished' (PA); after a previous Mechanic has already performed the same maintenance that is required in the assigned Task Cards.

Narrative

Previous afternoon shift [had] completed oil service on both engines at terminal and notated in logbook. On two aircraft that I recall; while working the night shift; Aircraft Y and Z; there were multiple sequential tasks [(work cards)] that I signed-off with a line and single signature/employee # on the Periodic Service (PS) Check as Previously Accomplished (PA); and referenced the actual logbook page in the signature block in what I thought was per our Procedures Manual (PM) XXXX. Unfortunately; I didn't notice that Procedures Manual XXXX.11.G; specifically excluded [signing] PA from the actions that are eligible [to use] to sign-off sequential tasks with one signature.The next day; while reviewing other parts of the PM; I noticed this conflict. This is a new process; with many confusing and conflicting bits of information as to what is supposed to be done when a previous person performs maintenance set forth in a work card later assigned to [another Mechanic]. In the near future; a Separate Check (SC) will be issued every time Oil Service is requested/required; and this situation may become more confusing and potentially cause more possible Non-Compliance issues like this one... First: I would suggest that Previously Accomplished (PA) be removed from the Procedures Manual XXXX.11.G. exclusion; as the requirement to cite WHERE the [Maintenance] action was accomplished [as noted] in Procedures Manual (PM) XXXX.10.A; should be usable through multiple sequential [Sign-off] blocks.Second: a thorough examination of the processes; that caused this error and other sources of confusion; be done and a structured process be implemented and explained to the work-force [Maintenance employees]; either via E-training and/or Shift-meetings.