WuDStefoto,
what RedBarmaley means is this:
The Devourers use their Ability "Acid Spores" at 20 seconds in Battle.The ability acid spores does not apply to every unit of your group of destroyers. Only to a few of them.
This few affected units now have a 50% increased attack time. When their attack time is "anti-phase" with the other ones then the attack damage dealt by the few destroyers is, of course, significantly lower than if all destroyers would shoot. You can imagine that as a group of units inside your group of units. One time the small, by acid spores affected, group shoots solo, then it shoots together with the others and then solo again.
Example for anti-phasing (with 20 seconds attack time because the times are easier to understand):
Unaffected shoots at 20 seconds
Affected shoots at 30 seconds
Unaffected shoots at 40 seconds
BOTH shoot at 60 seconds
Unaffected shoots at 80 seconds
Affected shoots at 90 seconds
Unaffected shoots at 100 seconds
Both shoot at 120 seconds
= you can see that only at certain moments, basically every 4th attack, the times of the affected units and the unaffected units overlap. In all other cases, so 75% of all cases, the affected and unaffected units will shoot seperately. Their damage then depends of course on the amount of units in the groups "affected" and "unaffected". Not all of your destroyers are affected by the ability Acid Spores.
If you now calculate the attack times that would occur for your destroyers you get that at 62.5 seconds a attack of the ones affected by acid spores will happen. But the other ones will not attack at this moment.
Therefore the attack only of the affected ones will be shot at 62.5 seconds.
Calculation: 25 seconds + 25 seconds * 1.5 = 62.5
The unaffected ones attack normally at 50 seconds and at 75 seconds.
This is also shown in your battle report. I marked it for you here:
http://prntscr.com/mocdpq