Hi
Annie Woodcock is on the electoral registers at 5 Richards Cottages, Acton, 1918-22, bot not thereafter.
However, looking at the 1921 census free index, she doesn't appear to be there with James and the rest of the Woodcock family.
She might be Annie Woodcock, born 1869, birth place Not Known, parish Wandsworth Borough, Reg. Dist. Wandsworth.
The LMA catalogue has been known to go down for short periods, weekends can be dodgy, should be up again before long. You can then check for the Springfield records.
The local poor law union would be Brentford, unfortunately not too many records survive, and I can't see anything relevant online.