Indeed, I projected based on reported cases increasing by 1.28 per day but in fact it is as you say estimated to be 5,000 to 10,000
Until there is a mass produced vaccine or we have herd immunity (which would mean 40 million uk citizens having had coronavirus, recovered and developed immunity) then it will continue to spread but hopefully as more people get it, recover and develop immunity it slows down.
Problem is that with 3% of reported cases being fatal, it is estimated that maybe 1% of total cases are fatal - that is 400,00 UK citizens. Could be many more times that require hospital treatment and recover but NHS does not have that kind of capacity. So slowing it down (flattening the curve) and minimising transmission to the vulnerable is key.
https://www.statnews.com/2020/03/11/flattening-curve-coronavirus/
But this slowing down may mean it impacts next season as well.
I have seen unsubstantiated reports of the Chinese using blood from people who have had it and now have immunity and antibodies in their blood as a treatment...
https://fortune.com/2020/02/14/china-coronavirus-treatment-blood-plasma-recovered-patients/