I suspect they don't have much experience with USA applications. Though they are grossly misleading their clients. The USA has some of the fastest processing times of any country in the world with UKVI.
Did they have you include a property inspection report for where you will be living? If so, that's a big red flag.
Apologies for long silence; life is chaotic right now. We were asked to provide "Estate Agents report confirming the size of the UK property (i.e. how many bedrooms, reception rooms etc) – this is so that we can demonstrate that the property will not become overcrowded under the Housing Act, and needs to be proven for the application."
We didn't pay for this. I just asked our landlord to forward the document from when he purchased the house 2013, which he did. Our application folder was enormous. It was packed with documents such that the guy at the UPS office said it was the largest visa application he'd ever mailed. At the time I wondered how on earth such a large folder could be processed in the quick window they'd suggested, but figured they knew what they were talking about. Now I realise it was probably packed with unnecessary things that could slow us even further.
In response to my email to them querying the original "2-3 week" processing time suggestion, they replied saying that they have had applications go through that quickly ("although 3-5 weeks was more standard" [even this seems ridic looking at current processing times]). Of course, they pointed me to the small-print in our contract which did re-state the "up to 12 weeks" that we always knew was a worst case scenario.
In the meantime, I have gone ahead and booked a flight for myself for 10 days time (our stuff is being shipped and I need to collect it). We have made arrangements for my husband and son to remain in the US and follow once his visa arrives. The cost of making these contingency arrangements, accepting a loss of income in August, arranging emergency health insurance (our runs out tomorrow) etc, on top of their fees, is eye-watering. And I am not relishing being separated from my toddler for a prolonged period. If we're working to a 30 day best case scenario, we'd be apart for 2-3 weeks minimum.
Moral of the story - always do the research yourself.