I think businesses will start to reopen by end of May, at first cautiously with limited hours, but then gradually get back to normal.
If the stimulus works as intended, the economical damage should be significantly mitigated, as many business would be able to rehire all or most of their employees whom were thrown a safety net. There will still be severe economical casualties. Might take a decade to get back to where we were.
There are factors at play that can affect the outcome. There may be a huge demand to bring manufacturing back home, which would crush China and restore our economy, or China might actually gain in dominance over manufacturing. Hard to say at this point.