I think this is the first time we’ve seen someone in the Central Military uniform. Typically it’s just sort of green-ish and uniformish looking, the yellow slashes represent a particular unit inside the organization, not a rank. Central Military is actually not part of the I.D.S., but Situation Containment members belong to both, as they tend to be a little too well armed and capable for an even technically civilian branch. People like Kally who are not currently in the either the military or S.C. are retained on reserve – a powerful mage is rarely ever discharged entirely. Arron is a different case in that he was always technically active, but not generally expected to use his rank as a Major over his rank as an IDS Director, as he was more a representative/observer of the military due to the very limited presence on Palindra. That said, he is far better liked in the military than the I.D.S., though mostly among older members.

I debated for awhile if it made sense that Kally would change to her uniform (or even have a uniform, considering she wasn’t on active duty). Than I remember this is Kally, of course she would (to both).

The ranks of the S.C. (and Central Military) are a bit odd, as there has been sort of a rank Inflation due to original practice of mages being given an artificially high rank, now that most of the military is somewhat magic-equipped it’s faded a bit, but it’s fairly common for a squad to have several Corporals or even mostly be made of them. This holds doubly true for someone like Kally (whose rank we haven’t seen yet), though as a specialist (special) officer rather than a command officer, she is not typically any command of anyone (and thus is not necessarily trained as an officer).