After a while, all new fleets that I create after recruiting an admiral get named PXXXXXXXXXXX (I assume invalid characters). All the old fleets still have their proper names. Also, if you hover your mouse over the name, you get a small window stating 'p ', while regular names do not have a hover-over.

Additionally, not sure if this is intentional, but all Adeptus Mechanicus recruitment portraits are the same, rather than being randomized as other factions.

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