The question, however, remains when and how. And they accomplished this without a hitch. COBOL training, however, is starting to make a comeback. No STC should find their customers in the situation that the state of Connecticut found itself.  Fear of the unknown.
essential backward compatibility is not mentioned.
( z0 mention :ARG1 ( z1 compatibility :mod ( z2 essential ) :time ( z3 backward ) ) :polarity - )
(z0 / mention-01
    :ARG1 (z1 / compatibility
              :mod (z2 / essential)
              :time (z3 / backward))
    :polarity -)
essential backward compatibility is not mentioned .
z1 :time z3
z1 :mod z2
z0 :polarity 0
z0 :ARG1 z1