Still pondering that fatigue issue. EAM you mention 5 nights in a row. After a week like that, do you get time to recreate? What is the birds eye view on your rosters, say in weeks. Is there a week off after a full week of night work or is it pretty much like a regular job (5-2 days, more or less), just that the work hours are after dark?
If the latter applies, this would make the job similar to those gigs in ports or 24/7 plants, where some people are on a „night only“ crew, and adjust ALL of their lives to being night owls because there simply is no time to readjust. In fact, those people are told to adjust to nights 100% because 2 days off between weeks might just confuse you more if you try to switch to regular daytime activity.