Why did the monthly payment date change after the transfer to Uralsib?

The monthly payment date remains the same, but funds are debited only on business days.

For example, you usually make your loan payment on the 1st. This month, the payment date falls on a Saturday, so the funds will be debited on the next business day, Monday. The same applies during public holidays, for example, in January or May. If the 1st falls on a day off, the funds will be debited on the first business day after the holidays. If the payment date falls on a business day, the payment will be processed as usual.

The date shift does not affect interest — the loan amount will not change, and you will not overpay on the loan.