I believe the field techs which we are accustomed to seeing do 10-hour shifts from 8am-7pm (8am-6pm on Saturdays) with Sundays off (unless doing overtime). Furthermore as VM has a 24/7 operation there will be people on duty doing shifts.
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Hub 3.0, TP-Link Archer C8, TP-Link TL-SG108S 8-port gigabit switch, V6