Indeed it is. This is in regards to goods billed in 2019, mind. Just a little heads-up from someone who's spent the last weeks adjusting BTW tariffs for companies to use XD

So you might want to do a little tally and either bill people who ordered from you in 2018 now, if they're expecting the old tax prices. Or warn them that they might see a retroactive price-hike for being billed in 2019.

That is a good point. Thankfully, all of the 2018 invoices are taken care of already.