None of these following flags are listed in the patch notes, I also checked all news posts I could find aswell as the contests on the WoWS forums.
Whoever can identify any of these flags, please comment below and I will update the flag descriptions within the post:
Flag 1 – Premium ship Graf Spree’s “I’m Rich!” flag:
Flag 2 – CoinsUp Logo
Flag 3 – Premium Ship Oleg’s “I’m Rich!” flag.
Flag 4 – Project Oil flag, an event happening on RU.
Flag 5 – 75 year anniversary of Pearl Harbor.