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The last nine days of the three weeks—which are also the first nine days of the month of Av, culminating in the Tisha B'Av fast—constitute therefore a period of intensified mourning in the Ashkenazic custom. Many Jewish communities refrain from partaking of poultry, red meat, and wine; from wearing freshly laundered clothes; and from warm baths. Sephardim observe many of these restrictions only from the Sunday before Tisha B'Av, dispensing with them entirely in years when Tisha B'Av falls on a Sunday.
Rarely does the actual calendar date of Tish'a B'Av occur on Sunday. More often, as this year, 9 Av is on Shabbat and the observance of Tish'a B'Av is on SUnday which is 10 Av. Does this mean that Sephardim do observe the mourning laws beginning from the previous Sunday (which would be starting from 3 Av), or does it mean that they don't observe the mourning rules?