At "normal" airports, Tu & Wed tend to be the weakest days of the week. This makes me wondering how the situation at LCY is
London City's busy days for business traffic in the morning are Mon-Thu, less so on Fridays. This is because business travellers who are making day return trips tend to do this less on a Friday than on other days.
Those who have travelled out for the whole working week are laid on top of this, and will return on Friday (or often on Thursday instead, to have the Friday at their own office), but will typically return on the evening flights, so the demand for the morning flights drops off as the week progresses.
Weekend and other "leisure" traffic is laid on top of this again, there didn't used to be a great amount of this at LCY but it appears to be an increasing proportion. This tends to be an outward on Friday evening (not morning) demand, returning Sunday evening or Monday morning.
The upshot of all this is that demand for morning LCY flights tends to drop as the working week progresses, while demand for evening flights increases. So "busy days" have to be considered with different fluctuating demands within the day. There are other combinations. Friday evening may be the passenger peak of the week, but demand for business/first class on short haul flights at that time is actually quite low.