Thanks for this. it answered a few questions that I've be storing up whilst reading this thread.
FWIW I'm an average passenger who found this site when wondering what on earth was going on in the railways
With respect, I'm quite numerate and have decades of experience in operational organisations and I don't properly understand the situation around rostering, despite reading these threads quite assiduously. Please believe that this is not due to lack of interest.
Some other industries retain their rosters and can restart them with a small number of hours notice - nothing is stood down and in the event of a strike being suspended then staff come work as per their rosters. If they had been planning on a day off and can't make it to work then thats a different matter.
I am sure that it is different and more complex in the railway, I'm interested to understand in more detail as to why? I get the sense that the path of least resistance is to wind down the service early and enjoy the break but I'm not yet convinced that this is the only or best option.
A rough explanation, with a driver bias as I am a driver and for my TOC, other TOCs may do things differently but are largely the same.....
The train services that are required to run results in a Working Timetable WTT.
TOC Train planning departments will produce a set of diagrams based on the WTT each for rolling stock, drivers & conductors.
A diagram is just a daily list of things to do, for instance a drivers diagram will show signing on time, the timings and stop patterns of all the trains that the driver will work, it will show breaks and signing off time.
Train crew diagrams are governed by contracted terms and conditions, where you can sign on, minimum & maximum length of diagram, breaks location and length of break, walking times (yes!) Etc etc.
The number of diagrams that a depot has to work directly affects the number of drivers required, there is a formula and the number it spits out is the number of drivers required, it is called the establishment. The formula allows for sickness leave and spare cover.
It does not allow for any large scale training, this is where rest day Woking agreements are made between union and management. Such agreements allow for drivers to be released for training and for guaranteed leave by other drivers working their days off.
From a set of diagrams and an establishment of drivers local union reps (who are drivers) produce the rosters which are then agreed by management. Diagrams are allocated to staff dependent on route and traction knowledge and what Link they are in (Drivers are organised into Links [rosters] there are often several Links in a depot some with different routes and traction)
Once agreed the rosters are "hung" they usually run from December - May (the winter timetable and May to September (summer timetable) drivers can mostly know what they are doing for the next 6 months.
From those rosters the Roster Clerks will produce a weekly roster which allows for mods (diagrams modified for engineering works, strikes, storms etc) leave cover, sickness & training, to be allocated. In my TOC once you are allocated a diagram on the weekly roster it can not be changed (part of agreements that give a work life balance) but you can of course be asked to change jobs but can't be forced.
Finally a daily roster is produced showing the next days work, it should match the weekly roster but it allows for sickness and emergency leave, plus any emergency time changes to be allowed for. Like the weekly roster you can not be forced to work a different job, but you can agree too if asked.
This system is complex but it works, everything I describe here has been mutually agreed between union reps and management over many years. Part of the present dispute is the DFT via the Rail delivery group (RDG) wants to tear up all these agreements and terms and conditions that form the frame work for each step of the above process, they want to replace it with who knows what in the name of efficiency. We collectively feel strongly that the terms and conditions and rostering agreements are precious not only for ourselves and future colleagues but also the safety of our customers. Most TOC terms and conditions are based on the recommendations of Justice Hiddens report after the Clapham rail crash, it just should not be medled with.
Sorry to ramble on but perhaps it is a useful insight to one small part the vast and complex system that the Railway operations are.