Actually, Wikipedia link you provided just gives a list of ports and series of Contra, nothing in detail for the Amiga version. Next, I know it was released because:
A)The Amiga History Page shows the Release Date of it and
B)This guy from the Contra DB forum discussed his small playthrough of the Contra on a real Amiga. Said it was best in terms of graphics and sound, but lacked a proper ending. He showed a screenshot of the first level in the post, but the friggin forums is down indefinitely.
