Yes, I agree. The 1919H is by far the commonest of the 1918 and 1919 H and KN pennies in lower grades, but it's even harder than 1918KN in top grade. My own is EF+ without lustre for circulation wear, but there is practically no hair detail as the die used must have worn considerably, and the hair is the highest point. It's possible the Mint supplied some obverse dies to Heatons in 1918 and few or none in 1919, so there was considerable re-use.