[eftpotrm]

That only strictly applies during the regulated period of a campaign. As there isn't presently a relevant election ongoing and there isn't a candidate or referendum vote that it is directly promoting, they don't technically have to have an imprint.

Now, that's not remotely to say that imprint law isn't flouted during campaigns, I've absolutely seen literature going out that looked very like (though couldn't be proved as) party-distributed literature trying to influence an election but which didn't contain an imprint. But, this isn't a breach of that particular law.