Meh noob this noob that is all im hearing here jackals, very tactful if not very wise. A tip for you, in an Ideas and Brainfarts section you want support and input not alienate people everytime you open your mouth. This isnt saloon or D&D where things are very different and youd do well to understand for an idea to pass it needs a high vote, far as I can tell with your current popularity and attitude you've as much chance of that happening as you have your rep getting to 2 greens before reaching the 1000th post.
The idea is over complicated and your just digging yourself and your idea a bigger hole. If you wish people to rip it to pieces just carry on the way your going.My dear jackals Did you even bother with any kind of history or just go through your entire schooling without a clue how these events really unfolded ?
Glorry re the appointment. ill answer you as it seems Mr Dingo here hasn't a CLUE about history or anything to do with why battles are fought with 2 sides often all laid out exactly just like an appointment. Im sure youll get it pretty quickly.
It has often been the case battles have had an agreed and allotted appointment and start time throughout history, once the sides have massed and camped there is no sudden attack. These things take time to arrange even when there. Orders to be handed out guns to be placed and regiments to be formed, all of which takes time and cannot be done in secret. Sides would even arrange terms and location from time to time and yes even start times.
Forts are a huge team effort thats why you need an appointment such as an attack time attackers need the time to organise and form up, not exactly easy to hide... similarly you will have rarely found an attack of any such size not having defenders aware or whats massing on their doorstep. Its called having scouts and lookouts... unlike banks which as a rule get along fine on a day to day basis and have a much more daily role in the life of a town. It is really just a shop that trades money nothing more. Hence why having an appointment to rob one is imo just plain stupid and totally unrealistic in any shape or form.