Cheers Tom, I'll have a trawl on Connect.
Most signalbox special instructions used to be on the "Portal" but I don't think they are on there any more (or are so well hidden that I can't find them!)
Don't forget that a fair chunk of the generic rules that apply to a signaller are now contained in the "National Operating Instructions" (available on "Connect"). Location specific instructions appear in the previously mentioned signal box special instructions and are unique to the signalbox concerned, examples of things that can appear are instructions for signalling in fog or falling snow, propelling and shunting movements, working of sidings and yards, bridge strike appendix and any special instructions for working to adjacent boxes. If you are with the S&T, ask the signaller if you can have a read through next time you are in a signalbox. (As Tomnick mentions, cake or biscuits might help

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