A question about the Star Brigade Armor-Bot

Recently I bought a MIP Star Brigade Armor-Bot and I noticed something that I don't think anyone has brought up (although I could be wrong) on the missle launcher arm thre is a notch/groove that looks like something could have been attached to it (perhaps if the original line would have continued) If you have one look at it, I'd like to hear your thoughts on it (and please, no cracks about Star Brigade is crap, I merely would like to hear your thoughts/suggestions about this.

Thanks,
TK

While I don't know anything definite, there are 3 theories that I have:

1. It was going to hook up to another vehicle or toy that ended up being cancelled.

2. It was going to interact with another accessory within the Armor-Bot but that was not included for whatever reason.

3. The launcher was a piece from another toy line and the notch was a leftover from the other toy.

At that time, Hasbro was doing a lot of kitbashing to re-use parts of other toys where they could. Any way you look at it, though, this is probably another of those little design stories that would be great to know about the vintage line.