Great advice! Thanks I don't think much happens during weekends at these sites, so hopefully they se my email tomorrow before shipping it. Otherwise I will have to make a smaller batch, like you said. Nothing wrong with that eitherIf the parcel is already on its way, no problem in scaling this recipe down to 10-12l. It just means that you will brew the next beer quicker. When I started brewing, I made smaller batches on purpose, so that I can really evaluate each single change quicker. For example, I would start extremely simple, just like you, one base malt and one hop. Next time, I would either add one more ingredient or change one ingredient or change one major thing in the process. ALways only one at a time, so that I can compare what this one factor did to the beer.
You could change the hop, or the yeast, or add one steaping grain like medium crystal for example. The more batches you brew this way, the quicker your knowledge builds up and that is done the quickest with smaller batches.