Depends on what you mean by 'out of control'. The ability to stop the spread? The ability of the NHS to treat those that need treatment? The ability to stop all deaths that prevent a spike in numbers? The ability to measure who has died of COVID-19 rather than primarily because of another condition? and so on.There's "only" 477 deaths so far in the UK from COVID-19, so we shouldn't expect to see a spike in the death rate caused by it. The objective of the UK government of course is to avoid getting into the situation that Italy is in with multiple thousands of deaths.
If a spike is seen, then it will mean that things got out of control in the UK.