Everyone I know has had that happen at one time or another, and it’s extremely common to want home battery just for the degree of ‘power sovereignity’ it grants you.
You can read up on the subsidy itself too - they basically set a cost per kwhr target based on the few bespoke batteries on the market, before it was flooded with cheaper Chinese options. Because it was based on capacity rather than a percentage discount, this caused the effective discount to be much higher than intended at the outset.
We don't know the final numbers yet - but government has reforecast for 7 billion for the program's duration, which includes a much smaller subsidy continuing until 2030. I expect it will be close to about 5B spent so far.