I doubt the answers provided by almost all the institutes of the question about minimum number of days the Parliament is required to meet.
The constitution does mention that there should'nt be more than 6 months gap between each session, and that does imply that minimum number should be 2. Idk why anybody is not discussing about this.
Because ultimately to attempt the questions of polity, one must refer to the constitution for clarity. We can't get answers if some news article or website mention it verbatim.