B"H
The Maharsha teaches that the 21 days of the Three Weeks of Mourning can be compared to the 21 days from Rosh Hashanah to Hoshanah Rabbah. Following this logic, we see additional parallels:
The 17th of Tammuz is Rosh Hashanah.
The 25th of Tammuz is Erev Yom Kippur.
The 26th of Tammuz is Yom Kippur itself.
Erev Rosh Chodesh Av, the yahrzeit of Rashi, is the 13th of Tishrei, yahrzeit of the Rebbe Maharash.
Rosh Chodesh Av is Erev Sukkot.
The 2nd of Av is Sukkot.
The 5th of Av, yahrzeit of the Arizal, is the 18th of Tishrei, yahrzeit of Rebbe Nachman of Breslov.
Erev Tisha B'Av is Hoshanah Rabbah.
Tisha B'Av, the 22nd day, is Shmini Atzeret.
