When an untoward incident happens to a distant relative or known people while we are away, on which days should we call upon them to convey our condolences as we are unable to visit them in person?

There are many opinions regarding this subject. Each place/region follows its respective practices; while Srirangam has its observance and Kanchipuram follows as per their observance. Some say one has to convey their condolence during odd-numbered days like (1,5,7) while some others say it has to be on even-numbered days and few more say it can be done on any day within the first ten days period after demise. But many believe Mondays are not prescribed to convey their condolences, hence Mondays should be avoided.
According to many, any other day than a Monday is suitable, however, it is advisable to follow their respective practices.