From a major UK airline. "Variations of up to 10% for a non
-mandatory task can be authorised by Engineering Quality.
Variations of more than 10% for a non
-mandatory task must be authorised by the CAA.
Authorised Maintrol staff can within authorised limits,
grant a Maintenance Period Time variation to ramp
check, daily/weekly checks and life controlled items.
Any variations outside AMP specified limits, or to
a mandatory requirement, may only be granted by the
CAA.
Variations for other operators aircraft that are ma
intained by XX, must be approved by the operator of
that aircraft."