A few years ago the domestic bank transfer have been done overnight. The first big step forward was to make it within 4 hours during working time. The system now works on hourly basis: all the domestic payments via bank transfer are fulfilled within an hour.
The next milestone will be 1 July 2019. By then, all these transactions have to be executed within 5 seconds. Actually, all the payments will be debited to your partner's account immediately.