Updated: May 4, 2020
The frequency of visits depend on the year and the place of origin. In the first year, the courses are compulsory and laid out evenly, with at most 3–4 holidays in between any 2 terms. Apart from that, there is a break for Diwali for about 3 days. I remember going back home (which is about 1,200 km away) almost 4 times in the first year. The first visit was in September mid (which is 3 months after the joining). The longest I've been home was just before my internship began (almost 7 days).
In the second year, you get to choose your courses. This allows for many days when there's no lecture at all. You can choose to visit your home during this time. I'm done with 3/4th of my second year and have already visited my house more than 5 times. Each time, the stay was for more than 5 days at least. Since the courses are elective, sometimes there is a lot of gap between my last exam and the beginning of the next term. I've got as much as 20 days off because of such scenarios.
Some students also take up courses keeping in mind the holidays they may be able to get (for various different purposes like visit to home, internship, foreign trip). This is called front-loading (taking up courses that finish in the first half of the term) and back-loading (taking up courses that take place in the second half of the term).
Some students visit their homes evenly in both the years because their homes are nearby (e.g. Mumbai natives often visit on a weekend). Some students choose not to visit their homes more than 1–2 times a year because of various reasons, financial reason being one of them. The propensity to visit increases in the second year once we've done internship and have earned some stipend.
In general, I've not heard people complain about their inability to visit home as much in the second year as I have heard in the first year.
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