I know it's been mentioned before on here, but why do they announce new rules to supposedly help contain the virus that come into force days later??? If it's a problem now that you have to change the rules, then a few more days is only going to make it worse.
Quarantines for countries, mad rush of people trying to get home so they don't have to quarantine, probably on packed airlines to get as many people back as possible, from an area that has been deemed unsafe and an increased risk of infection. So if those people did get infected and got back before the quarantine, they could just then stroll out and infect others.
Areas of increased lockdown or the rule of six have led to multiple warnings about not having large gatherings or going out before the rules change, which is exactly what people went and did. (Obviously not everyone).
These new rules, if shop assistants not wearing masks is contributing to infections, then make it mandatory now. Luckily pubs rule isn't coming in after a weekend, but again if people are spreading it more after 10 as they get drunk, then change it now.
It may cause some disruption to people and businesses, but if it's needed to stop the virus, then why put it off any longer than necessary?