If you look up Computation of Days in RONR 12, you will find three sections that basically say the same thing. I'll quote one below.
These all deal with notice for meetings. Here is what I can't find: if a motion or rules of a society require action to be taken within x number of days, how are those calculated? At first, it would appear obvious, but thinking about it, I'm not sure it is. Taking guidance from above. All days, excluding the day of the meeting, should include the day of the notice. What are the analogs here? Is the notice the day of the motion or trigger to the rule, and the meeting is the action? In that case, it would seem if the rule said 30 days, you would include the day of the triggering action, go out 30 days, and if you did it on the 31st day, then you would be safe because you don't count that one. Is it the other way, such that the day of the triggering event is the meeting, so you don't count that one, but you have to do it on the 30th day? Or do you get one less day for taking action than you do for noticing meetings? Any help or references would be much appreciated.