Attacking an Independent Castle.

[Yakone]

I have read the rules over and over but a small clause causes confusion.  I understand that the castle stays at f8 regardless but in order to conquer the castle, the amount of troops IN THE CASTLE when less than 1000 the castle falls.  Field troops are irrelevant to this calculation.  Is my understanding correct?

[Angela]

The independent castles don’t have allegiance and because of this they are conquered when less than 1000 military units are left in them, meaning 1000 military units total (garrison army + field army). To perform a successful fortress siege, the field army has to be destroyed first, but after winning the battle, some of the field units in the independent castles also recover, as some of the garrison army does.