RBI gives daily data on the no of transactions and value of transactions across various payment methods. It is instructive to study the same.

https://rbi.org.in/Scripts/Statistics.aspx

In the case of UPI, the no of transactions are at the highest at the start and end of the month. The transactions continue to remain steady for the first 10-12 days and start declining for the rest of the month till the spike at the end.

It is not surprising given UPI today accounts for 15-20% of retail transactions. The month start and end spurt is mainly due to period payouts such as rents, help salaries, credit card bills. Hence it mimics the likely transaction frequency of an ordinary person.

Interestingly ATM withdrawals also show similar trend lines with much steeper drop across value and volume, again as most people would withdraw the major share at the start of the month with only top ups in between.

RTGS, the highest medium by value however is pretty stable except the off days during Sundays. This again reflects the business and corporate transactions which don't vary as much.