I only ever used agency work when at a loose end on the vans and at that point I never worried wether they were advertising I just rang around regardless and they’ll usually just sign you up anyway, haven’t needed to use them with my HGV as found my own opportunities by approaching employers directly even if they weren’t advertising, going in to see them makes a good impression, you can have a chat in person and at worst leave them a cv at the end. You never know if they’ll be stuck for someone when you arrive!
Using this approach I’ve always heard back from employers eventually and turned a few jobs down as I’ve been happily sorted already.
Good luck with it all.
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