There are lots of threads on here about second UK passports but most are somewhat old and most are about getting one rather than renewing one so I thought I’d ask if there are recent experiences.

I live in the US (Boston area) and currently have two UK passports, the second obtained while still a UK resident and when I was travelling a lot on business. One of them now only has 2 pages left and they are not facing pages, so it’s no longer any good for China visas. Changes at work mean that I will need to start travelling to China more frequently again, and the New York Chinese consulate will only give me a 6 month, 2 entry visa each time. I’ll almost certainly be burning through visas faster than I can apply for them with a single passport.

Because overseas passport renewals now have to come to the UK anyway, what are my options? If I send the full passport back for renewal, including a colour copy of the other passport (so I can keep and use that in the meantime) and a company letter requesting I be renewed but keep the other passport active, should that work? Is the 4 week processing time on the gov.uk website real? I don’t have any trips to the UK planned and I’d prefer not to make a special trip.

On a side note, has anyone done this before with China visas? Do they notice and care if a person alternates passports for each visa application?