The best thing I can say about insurance is - ask.
I recently needed something a little 'off piste', shall we say - and whilst I'm not going to go into detail, suffice to say computer said no.
I spoke to Tony at Greenlight, put my case forward with a detailed email and he took it to the underwriters with his support due to me being a long term customer with excellent history. Computer no longer said no, I got what I wanted, he got to keep a happy and loyal customer.
I'm not going to pretend they're suddenly all up for taking on more risk if you just ask, but some cases are borderline and with a bit of discussion can be sorted.