You don't have to worry about it because miners and cloud mining service must have solution for bitcoin reward halving.
Also, bitcoin price almost doubled from 2 month ago where the price was about $400

So the cloud mining will have a solution? I asked a few did not reply, ask more famous cloud which mining companies?
Most of the cloud mining finally turns out to be the scam. This is being left over various investors in dull to think about investing in such cloud mining. Very few genuine available now.
Yes you can either earn from providing some service and in return get bitcoin. Or though campaigns other than purchasing it.