Did this in the practice range on PTR and I don’t think it’s an intended function.
First Oddity
If you throw a repair pack on the friendly training bot, wait until just before the decay starts, and throw on a second repair pack, the duration from the first repair pack will still be used and the second armor boost will effectively be wasted.
Second Oddity
If a friendly bot takes damage but still has armor remaining, and a second repair pack is applied once the first’s armor decay has started, the amount of armor the friendly bot had before will be retained for the second armor pack. It does not apply a full set of new armor!
The first oddity acts like Armor is exempt from the bonus 2 seconds added by the repair pack but the second oddity keeps the old armor value during the armor’s decay. If these are intended functions, they are heavily conflicting seeing as the first oddity ignores the 2 second boost but the second oddity applies it.