No reason she couldn't be Eleanor. I have no evidence of this but I may have more to go on when I get Irene and Harold's marriage certificate. They doctored the physical copy that my Grandfather had, to show that they were married prior to his birth! I don't have the copy they altered unfortunately.
Both of them lived until the 1960s, so Irene didn't die young and leave Harold Sr to raise him.
Peter was born quite a bit later, December 1926. I have attached a photo of his birth certificate.
It's unlikely that Harold Senior fathered Harold Jr because my Mum reports that Harold Senior was very badly injured in the war and didn't return until 1918, so he wasn't in very good condition!
Where did you get the 49 Upper Park Road info? Interested in looking at that. I'll send more details as and when I find any.