Looks like problem is with you and some of your service guys! I've work
both sides of this fence and they sometimes may need to make those
changes, BUT should get approval to do so first, if they can at the time
needed. This is a communication, documentation and training problem.
A good plan is to to have time-dated read only copies of both the
running and previous programs as to be able to make SW fixes but be able
to go back if changes do not workout with the test of time OR are temp
fixes. In many places these are stored at both the machine and a safe
secondary location(s). There is also PW protected SW to do this, ask an
IT guy or SW developer.
One common example is when an I/O point dies, no spare card is currently
in-house and they might need to move the point to a spare I/O in order
to get production up and running NOW. This is a temp fix for the effect
of a yet to be determined root cause problem that needs to be found.
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