Have you asked them:
https://www.poseidonbike.com/pages/get-in-touch
Also what does it matter it is a super low cost alloy frame if you are going that low for a bike you have to imagine it is not coming out of a place of quality or good practices. Don't expect it to be some artisan frame builder more likely a hot factory with poor working conditions and there has been at least a couple worker deaths that were swept under the carpet .