From (the real) Gridwatch, it appears that Gas outperformed Wind for a
15-day period, from the 8th to the 22nd inclusive.
Judging by eye, the difference was an average of 11GW, for a total of 4TWh.
In December there were four short periods where Gas had to step in again, for an estimated 2TWh.
And in November there was another series of days, totalling 18, where Gas was the main provider, for some 4TWh of Wind shortfall.
Since there was insufficient surplus energy available to recharge any battery farms that could have supplied these shortfalls, it would seem that battery storage is a non-starter as backup to Wind.
Rachel Reeves was on the radio this week extolling the virtues of Hydrogen.