I played in a tournament on Sat, and a scenario came up that I was unsure about since I've only played a total of 4x games in 6e (3x were on Sat.

)
On my turn, I charge 5x Terminators w/
TH+
SS into a unit of Draigo w/ Pallies & Coteaz.
The Terminators are within 12" of Kantor so would get +1 Attack, so on the charge that would be 4x Attacks.
My opponent throws his grenades and subsequently rolls a 2 on the chart.
Lost in their own private hilarity, the enemy unit is hit automatically in this assault phase. They can still fight, but with a Maximum of 1x Attack per model (to represent their flailing).
Okay so now their attacks are down to a Maximum of 1x Attack per model. That seems pretty straight forward:Maximum, Total, etc. that is... I very much understand what maximum means.
However, I was unsure of how this interacted in 6e. In 5e, I think it's clear that it'd only be 1x Attack. In 6e there's now the following rule:
"EXCEPTIONS (page 9)
While playing WH40k, you'll occasionally discover exceptions to the general turn sequence laid out here, when things are worked out as they occur rather than in any strict order. At other times, you'll find that both players will have to do something at the same time. When these things happen, the player whose turn it is decides the order in which the events occur. Occasionally, the actions of one player will trigger the sudden appearance of a particular unit, or may activate some special rule or occurrence. When this happens, the exceptional rule will contain all the information you need to resolve it."
What I proposed how it worked was: since I was the active player, I charged his ability triggers and effects my unit. As the active player I could now say that my effect (Kantor) happens afterwards, ergo giving the Termies +1A again. Of course, this scenario would only work on my turn being the active player as of course my opponent would choose not to have this order in his turn. I realize the two systems are completely different, but this felt very similar to persistent effects in
MTG and the active player.
I was unable to reference or find the rule at the time of the game, so since we were both friends & adults simply agreed to roll off.
I am however interested, in the correct way to play it.
Can the maximum attack effect happen before the +1A because of the Exceptions Rule?