EricP. Unlike many, I have a number of years experience of your problem, based on that, I wish you luck trying to contact a real person at the British Consulate and getting advise in your personal situation, and not just a referrence to the general info provided by UK Gov.
I am in the same situation as you and after ten years married to a non EU citizen we have booked flight to UK for later this year. A problem which we had previously encountered when we considered such a trip , was that BA said they would not let my wife board albeit that she had a valid PP and an Article 10 resdencia, so would be alowed to enter UK.
For my proposed trip I have been trying to get EasyJet to confirm they will let my wife board. They refuse to give a straight answer.
My email to EasyJet:
I have Irish and UK passports. My wife has a Philippines passport and permanent status Residencia in Spain. Please confirm my wife will be allowed to board with her passport and Spanish Residencia card.
Please see; http://curia.europa.eu/jcms/upload/docs/application/pdf/2014-12/cp140182en.pdf
Reply:
With regards to your wife's travel documents I can confirm that all passengers on international flights must be in possession of a valid passport and, where required, a valid visa, unless you are flying solely within the UK you’ll need a passport or an equivalent travel document that is in good condition. For visa requirements, contact the Consulate or Embassy of the country you are planning to visit.