[Remind-Fans] Question about omitting floating holidays

[Geoff Ball]

My work schedule is included in my Remind calendar like this:

REM Mon Tue Wed Thu Sun FROM Dec 3 2007 SKIP MSG Work 6-2:30%

I have a list of all holidays in holidays.txt, which is included into  
my ~/.reminders file.  In this file, I list out all the Canadian  
holidays and "special" days.  A normal holiday where I would have to  
work is listed like these:

REM Sun 8 May +3 MSG Mother's Day %b%

and

REM Nov 11 MSG Remembrance Day%

I'm now trying to incorporate the holidays where I would not have to  
work.  I have looked through the man page, and am using:

REM Mon 1 Sep SCANFROM [trigger(today()-7)] SATISFY 1
OMIT [trigger(trigdate())] MSG Labour Day%

I'm not using push or pull-omit-context, as I don't see the necessity  
here (although if it would help, I can change that).

My question is: how do I know when I have to increase the numeric  
value (in this case, 7), and what are the consequences of making this  
number bigger or smaller?  My main concern is Easter, which can span  
over about a month.

As a follow-up, I was using the following before, which seemed to work  
okay (despite the man page, which said it only works one time):

REM Mon 1 Sep SATISFY 1
OMIT [trigger(trigdate())] MSG Labour Day%

This seemed to work fine for me.  Any input would be appreciated.  I'm  
using Remind 3.1.5.

Thanks,
Geoff