Strange tread block wear

[3VILC]

Got some odd wear on my front tyres, on the inner row of blocks, all the even blocks are worn lower than the odd blocks, but are all flat not feathered or uneven. This is only on the fronts and only the insides. Any ideas what would cause this? Tyres are nankang n889s in 33x12.5s

[firestonecruiser]

put up some pics of wear pattern as i work at firestone and do a bit of suspension work plus i am there wheel alignment tech.