Tier 4 student went over the 20h work limit once

Hello everyone,

I am a non-EU undergraduate student on a Tier 4 for an exchange year in the UK. I started working one month ago at a pub with irregular working days / hours, I was aware the visa only allowed for a maximum of 20 hours per week of work during term time but I assumed the "week" was defined as Monday through Sunday - it was stupid not to check better before, but my manager confirmed as far as the pub is concerned that's how the week is defined. Now I know for the visa a "week" is any running 7 days.

Now here is the thing. I looked back and I went over the 20 hours only once - to be exact I did 20 hours and 32 minutes. It so happens that 1 of those hours happened on the last of those 7 days after midnight. So, from Saturday to Friday I worked 20h32min IF they consider the one hour after midnight as part of Friday (I mean I worked from 00:00 to 01:00 of Saturday).

Should I be concerned? Should I contact UKVI? I'm wondering if I actually need to worry considering (1) this only happened once¹, (2) it only went over the limit by 32 minutes and (3) technically I went over the limit after the seventh day was over.

¹ I definitely will pay close attention from now on that I don't go over by even one minute.

P.S.: I just sent my National Insurance number application by post today. Will they check my payslips?

Thank you in advance for any assistance.

Is this a rag week prank?

This is not a prank. I'm asking it here because I couldn't find any similar cases (all I could find was people who would regularly and/or (more commonly) intentionally go over the 20h/week).

Technically it is working in breach so technically it could lead to the curtailment of your tier 4 visa.
Things to consider.

It is highly unlikely that your oversight is going to be investigated and given the one off limited nature of the matter it is equally unlikely going to lead to visa curtailment.

However if the pattern continues your risk increases massively as does your employer. The employer can be fined if they allow working in breach as can you be too.

Moral of the story - don't risk it because a £1000 individual fine and kicked out from your studies and the UK is a very high price for a couple of pounds extra.