I work with a major UK publisher of consumer guidance and I proofread a range of their material prior to publication. Sometimes I am asked to turn them around on the same day due to a particularly tight deadline which means I have to work some anti-social hours. On other occasions I get 2 or 3 days to work on what they send me.
One thing they do suffer from is “shifting schedules”, when publication deadlines are moved back at the last minute because something significant needs to be done to the draft publication, e.g. copy re-writing. As a proofreader, I have to fit in with these “shifting schedules” and be flexible and be ready to react to a tight deadline.
My client really appreciates my flexibility and I have noticed an increase in the amount of work they are giving me.
If you value your client, make sure they value you too.