The time to perform a pointing will break down into 180 seconds for target aquisition, and 25 seconds of security time. This security time takes into account the pointing margins mentionned below. After 180 seconds one should know that frames are already being recorded.
There are security time buffers applied before and after each pointing
requests (PREQ), raster request (RREQ) or target request (TREQ, valid
for Solar System Objects), i.e. each time a slew that is not a
micro-slew is requested.
As an example, a time of 10+9 seconds has to be added to the
computed 
when the satellite slews either back from the
last to the first position of a raster, or between the source and the
reference in a beamswitching observation. Note that it is assumed
that these times will remain constant during a whole orbit. Were they
to change, they would become larger.