Commando mystery racing camshaft....

Mystery Commando cam, found in a junk engine I bought a truckload of parts. Notice how lobes have a flat on the top, maybe to help valve springs recover from harmonics? Looks like possibly a date of 2/70 along with some timing marks, just speculation though....No ideas on the "A"....

It looks like a radiused lifter type grind with the flat top. it also looks like the lobes were built up with weld and reground.