Good summary, Martin: I think you've covered all the major areas and most
of the minor ones too.
One alternative, which may be appropriate depending on how busy oncall is.
This is what I used to work at Digital back in the olden days: one week in
six was "offset working". Normal hours for that week were 16:00 - 24:00,
and on-call was from 24:00 to 09:00. For that we were given a 22% (from
memory) salary uplift. Any callout after midnight was paid extra. But, in
all honesty, Martin's guidelines sound fine.
-- 
Keith Edmunds
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