A friend and I were playing spades, and the below happened. The log pretty much speaks for itself.

It's your turn. You play a king of spades.
It's Stupid computer's turn. Stupid computer plays a 9 of clubs.
It's Friend's turn. Friend plays a 9 of spades.
It's Newby player's turn. Newby player plays a jack of hearts. [So should be out of spades at this point.]
xorg wins the trick.
It's your turn. You play an ace of diamonds.
It's Stupid computer's turn. Stupid computer plays an 8 of clubs.
It's friend's turn. friend plays a 10 of spades.
It's Newby player's turn. Newby player plays an ace of spades.
Newby player wins the trick.

Since I lead spades, the bot should have followed earlier (instead of playing the jack).

The ace of spades can be played whenever. you can save it and play it at some later point.

As well jack of trump in Jass/Apples.

Wait really? Is that mentioned in the rules somewhere or did I just miss that?

Not sure if mentioned in the rules, but its like that anyway :) only in these 3 games jass/apples/spades.

Yep tested it and it really is so. From my quick glance at the rules, doesn't seem to be there. Thanks for the info

owe my god, I also didn't know that. thanks for the info.