Harrold Oscroft possible name change

There is a mix up with my grandads family name although it was Oscroft at times it was changed, even in official documents to Ashcroft I dont know if it was origianally Oscroft or Ashcroft so I am leaving this message on the off chance that someone as information.He was called harrold Oscroft all his life, d.o.b.14th April approx 1900 he was in the 1st world war but came back to a Sheffield where he was born and married Ivy Dewrose, date not known any information would be welcome.