The government acts on infection rate data which inform projections from scientists. This information is used to propose changes to restrictions, discussed before public announcements. The government should provide a longer notice period, many restrictions have been imposed in under 24 hours.
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Overnight changes can cause unnecessary and additional damage to businesses, and therefore the economy. Irresponsible u-turns cause a range of added issues for citizens including the inability to travel home, compromised childcare and social care arrangements, job losses and threatened housing security.
The Government appears to act under the assumption that more notice will cause increased travel and socialising. However, the lack of notice can cause an influx in travel, and increased pressure on welfare, housing and social care.