Telling the time, once done with reference to the position of the sun or the shadows it cast moved on to clocks in the 1500 and pocket watches 1700 then wrist watches 1900 mainly for women, not becoming popular for men until 1920's, a brief obsession with the digital in 1970's to 80's settling back in the main to pointers and a circle of numbers to the present day.
However, for the bus commuter GMT is not necessarily the definitive method of gauging the time. After all the point of interest is not so much an accurate telling of the time but rather is the bus due or have I missed it.
In answering theses questions the regular traveller reverts to the human clock. If particular people are at a stop the assumption is made that the bus has not gone and is most likely due. The sight of others may have a different result. There is a lady I see regularly at the point I change buses. She wants the bus I am leaving, therefore if she arrives to see me standing she knows she has missed her bus. We therefore only have conversations when she has to wait for another bus. When things are running smoothly for her we simply exchange a good morning greeting as I descend from the bus and she prepares to get on.
On my homeward trip I sometimes use human clocks to help me decide at which stop to try and make the transition from one bus to another.
In addition to visual clues other people waiting for the bus may have a better understanding of how close to the timetable a bus runs at given points in the day or even the year. With an awareness of how school closure times, Christmas shopping, local football matches or concerts impact on adherence to the set timetable. This can result in a variation from the timetable that is in itself so regular it can be relied upon!