Soyabean spot basis bids fell to the lowest levels in more than two months at a closely watched processor in Decatur, Illinois, on Tuesday, pressured by limited demand ahead of the autumn harvest, grain buyers said. Bids fell 5 cents per bushel to a premium of 30 cents per bushel above benchmark Chicago Board of Trade soyabean futures, the lowest since July 6. The decline followed steep losses last week in bids for beans at many processors across the US Midwest. Corn bids eased 3 cents along the Illinois River, in Morris, Illinois, with harvest of both soyabeans and corn expected to be in full swing by the end of the month.