It is compelling for native English speakers to treat nouns that end in 'S' as plural.
To me it is obvious that those who coined this acronym, were aware of that, even to the extent that they fiddled with it, as you indicated to include the "P," an interior consonant in the word "anticipation." Thus it becomes a homonym to the plural of the noun form of "leap," i.e. "leaps," capitalization notwithstanding.
Otherwise, they would have named it "leas," which having no real antecedent in English would have been confusing to traders and other pundits.
So I think it is OK to refer to one LEAPS contract as a "leap."
This is very similar to the common usage of the acronym "snob". This comes from the latin, "sine nobilitate," meaning "without nobility" (pretending to be noble when you are not), or the British acronym "posh," meaning "Port Outbound, Starboard Home." This acronym refers to the practice of "snobs" (note the ad hoc pluralization) when they reserved passage to India via the Suez Canal, so they would not be exposed to the harsh Southern rays of the sun, being shadowed by the ship they were sailing in or out. In these cases, common usage has decapitalized them.
Steve G
PS. There is one very important singular noun that ends in s. It is "grits," a heavenly cereal made from limed corn, commonly eaten as a hot porridge, with or without cheese, througout the Southern states.