To obtain the subsidy you still need to establish a 30% drop in income, or be projecting that to occur in any month between now and June.
It is not compulsory to pay your employees 80% of their previous earnings. However, if you receive the subsidy, you must use best endeavours to pay employees at least 80% of their pre-COVID-19 earnings for the 12 weeks period of the subsidy.
However, if you can’t do that you must, as a minimum, pass on the entire subsidy to every employee for whom you claimed it.
You must keep those employees employed for 12 weeks.
The amounts are unchanged and paid in a lump sum covering a 12 weeks period.