Reserve lines are contractually required to be built with 14 days off within a pay period (28 days) and that’s exactly what they do. Note: there are a couple of oddball exceptions like a 35 day bid period and management flying compensation lines. Mostly they are arranged in a 2 weeks on/off scheme but there are some lines that split the 14 days into 2 blocks. Varies by fleet and time.

Airport standby = HOT standby lines = dozing for dollars. These are limited to 14 Duty days in a pay period and are usually broken down into 4 on 3 off schemes with 1/4 weeks completely off. Only 1 or 2 lines of these per fleet but it’s not uncommon to not see any. They company will drop HOT blocks into open time as needed but it’s for pickup only, no trip trading.

The HOT can only be a max of 8 hours of duty without a flight being assigned at which point it reverts to normal rest rules.