"JAL, can the Armenians be sown early like regular cukes?"
In my climate I sow pumpkins and winter squash May 5, Melons May 15, and cukes June 1. I sow Armenians May 15 with the melons. (If the soil and weather cooperate.)
May 18 is the average last frost, so that gives you something to shoot for.
Instead of Straight Eight cukes, I find Marketmore 76 to be a much better cuke. They seldom get bitter here. I think it is stress that makes cukes bitter. Try to keep the soil damp. I think drought stress, and/or excessive heat are the most common stress elements for cukes.
Gardening at 5000 feet elevation, zone 4/5 Northern Utah, Frost free from May 25 to September 8 +/-