A brief input...we are started heather harvest today so will not be posting much until at least the end of October.
First thing. I know the Portuguese supplier AND his supplier. The supplier at origin is a good one but we had similar...though far less severe..issues this year. We are of the belief that the problem mainly flows from the complexities and stress flowing from post Brexit rules, being enforced with zeal by the UK authorities. The issues with clearing them and delays in getting them into the country means they are spending too l0ong in transit, and then after that the importer has a full change of cages and workers to do, which also increases the attrition rate. (not a problen NI loophole users have).
The last two seasons, once we had all this cage changing to do, and having to collect in Calais due to failure of UK customs to guarantee prompt clearance, all cause delays, stress and death/damage in transit. We too have found the early queens now have a higher than we are used to rate of failure/supercedure/drone laying. All of these can in part be down to circumstances in transport.
Also relevant to the thread is that the main part of demand for queens is in April and May. Perhaps you could offer some degree of supply in that time period in the far SE of England, but in other parts you struggle to offer reliable supply before June. If you are in business for same year production colonies this is no use. Thus it is fine to advocate only using home raised queens but not all can do that effectively, and it is not just for reasons of incompetence/sloth/price. You need to be able to rely on your suppliers. Otherwise we end up in a very uncertain position which is not great if you are doing this for a living.
Another thing is what I have often called phasing of the market. Other than at a particular level of the market we face issues with years such as 2022 when demand for nucs/queens is relatively low, but we all had plenty bees in spring, and a couple of seasons back when there was high losses and lots of people wanted bees, but the same conditions hit the producers as well. So in years when availability is good demand tends to be low, and in years when availability is poor, demand tends to be high. Thus you need to find availability from place not in the same position you are yourselves. Hence we have home raised Jolanta breeder queens sitting out in Italy. Purely to satisfy early season demand.....and NEVER sold as home raised.
This is a massive topic....but you need to set aside the idea that the UK industry can met the entirety of UK demand. It cannot...probably ever. Will always need a two track approach to meet demand. Not everyone can afford to produce large number of overwintered nucs and queens. An overwintered queen for sale would need to be a very expensive item. The rate of failing to over winter is high..and the breeder is as well taking a full honey crop from it rather than sell.
We can only afford to run the Jolanta unit as it lives on the back of a major bee farm so there are cross benefits and funding for it in bad years. It may well produce more queens and nucs now than any in the UK, but without the bee farm to support it and add in the instability of fluctuating demand, but as a free standing unit it would go bust. We have invested a LOT of money in the domestic raising of stock, put our money into a risky project, but have no illusions about it succeeding as a free standing unit. Cross support will be a permanent requirement...both ways.
I also see that recent posts citing various issues around strain type. This is perfectly correct. Supercedure from this difference is quite common...you just need to keep knocking those cells down until the bees from the new queen hatch and take over. As pointed out, black bees are relatively poor accepters of queens they see as unrelated..including other black bees. Buckfasts tend to accept most types easily. None of that is hard and fast...just a tendency. Worst types I have ever seen for this phenomenon are Iberian black bees.