Incorrect.
the reason the 28 days was used was to enable rapid reporting of deaths….in the first part of the covid wave as deaths rise, it under reports then as cases decline it begins to over report.
I recommend you consider the difficulty of establishing primary cause of death.
let’s take an elderly person in a care home, they get pneumonia or urosepsis - is that the primary cause of death was it the late stage dementia?
let’s take a person in their mid fifties with Copd and high blood pressure, they get covid and die - what was the primary cause?