days / hours / weekends - confused please explain

[djrmrcbhyvf]

I know business days means Mon - Friday but not sure re just 'days' or 'hours'. I have a vague recollection that under 7 days is any day inc weekends but not sure about hours. Does, say, 72 hours notice given on Friday expire on the next Monday or Wednesday? Thanks

Under 7 days excludes weekends and bank holidays, over 7 days includes them.