300 War token left: Bug or am I missing something with the GW shipment?

Durango

Okay, first sorry if it's not a bug and it's something normal. But it really bugs me out (hqhq).

A few days, I finished my GW as usual, and spent the war token. I mostly spend them now in shipment of characters I already have at 7* to convert the excess in Shard Currency to farm Baze in shard shop, But occasionally, I use them for ship blueprint. I try to keep 400 token just in case a the ship I'm currently farming pop up in the shipment.

So I had 1600 token laying around, and the Geonosian Soldier's Starfighter blueprints appears twice on the same shipment, so I bought both of them, then spent 400 hundred in character shards, thinking I would have 400 left as usual.

A few hours later, I realized I had only have 300 left, which is absolutely not normal. So my question is: Where the hell did these 100 token went? Can something cost 500? For instance, do some blueprint are 500 token for 5 blueprint? Or did I spent 100 token on something I'm not aware of? The only other way (I can think of) to have such an odd number would be to start the GW, earn 100 + 200 going to the 4th node and stop. I'm adamant I didn't do that. Not only because I'm pretty sure I would remember it, but also because I haven't had trouble to finish the GW in ages. I have enough team to overcome the 12 nodes without too much trouble, even if I sometime have to throw like 4 team to the slaughter on the last node.

So this is a mystery for me and I would like to know if I did spent without paying attention (quite frankly, maybe I bought blueprint for 500 token, I can't remember) or if it's a bug. Having this odd amount of token drive me a little bit crazy so to speak.

Some folks on the SWGOH subreddit told me some shipment might ideed cost 500 token, but I've monitored closely for a few day now, and I never saw one costing more than 400. Is it super-rare ?

Thanks!