My 056 saws had unique flat headed screws as OEM. Many of the 056 saws I buy have T27. I assume the previous owner swapped them out for the convenience, as the proper T27 aren't free. Also maybe someone "BUGGARED" the original fastener for some obscure reason, or the saw rattled the screws out and they were lost, or some saw owner had a wife that loved her HUBBy so much she cleaned his shop for him and tossed everything in question into a trash can, BUT Counterair (SP?) to Bills analogy I firmly believe the 056 saws are not a late production model (as the Homie p'bly is) and I am very sure they are not prototype models. I would wonder if your saw has so many hours on it the threads were stripped in the case and some one was in such a hurry to get back to work they found some screw(s) close to the right size and poured Loctite in the holes and drove them "HOMIE" PUN Intended. As Bill stated "slooooow down" ... Nice looking saw for the money. Reminds me of a Stihl 020avp.