Interesting article.
The main western producers use yeast or e. coli to make the insulin, so I guess that they can increase production.
India and China have many companies making similar products, although one is not always sure of the quality, hence not available in EU, but is being made.
There was going to be a problem with production of animal insulins cos we are eating less meat then in the past, so less pancreases in the slaghterhouse meant fewer for insulin manufacture. A minor reason behind the switch to genetically engineered insulin.
The real rpoblem for the UK will be Brexit. The pound has dropped 20% against the euro and dollar and probably against the Danish Kroner so the insulin will be more expensive. (although still cheaper than in the USA); long delays at cross channel ports in cool lorries will add a bit to the cost, but the insulin has a very long shelf life.
The real problem is affordability in poor countries; Novo (and probably the other companies) do sell their insulin to poor countries at a very low price, but these coutnries eg Nigeria, will often add a lot of tax to the cost and make it unaffordable.
The Insulin dependent Diabetes Trust collect intact insulin to send to third world, so a really valuable resource; one year though, they were sending to New Orleans after the hurricane - a sad indictment of USA healthcare.
best wishes