Clarification on the rule of 3

Hi Nicholeen, I have a few questions related to the rule of 3.
Firstly, my husband and I seem to understand the rule of 3 a bit differently from each other and we can't seem to agree. The way I understanding which I wrote directly from your book is that when a child is out of control. We give the prep followed by instruction then correction 3 times. if the child has still not calm down, we walk away for some time then come back and start the whole thing again and if they are still not following instructions we go away a 2nd time and then repeat the whole thing one last time and if they are still not complying we then apply the 24 hours lost of privileges. But until then we only give give them chores as consequences.
However, my husband thinks I have misunderstood and that the process I have just described is too long and that we only need to go through the pre, instruction and correction 3 times which could include walking away for a time between those times and at the end of the 3 times apply the 24 hours lost of privileges.
Secondly, both our strong willed children (the older is also diagnosed as ODD)say to that when we ask then to take deep breaths, that makes them even more angry so we have changed to giving then 2 or 3 minutes to calm down instead. However, I sense that may be them wanting to take control of the situation and not wanting to follow instructions. What do you think?
Thirdly, when they earn a maintenance consequence we want to check that they should do it straight away, but I guess as soon as they are calm and not while they are still angry?
Lastly, regarding the 24 hours lost of privileges, my husband has been telling the children to let us know when they are ready to start the 24 hours, however sometimes they forget and so that means that the 24 hours end up starting later and therefore it prolongs the time. Should we continue with this or should we tell the children when the 24 hours should start when we see that they are calm?
Thank you