Since having a scheme cars, I have continued to run my own private vehicle and to be honest never considered insuring with schem inurers. That said I’m not a fan of DL since having home insurance with them many years ago. FWIW, I have Esures 5 star cover for both home and car currently.
Given you have built no NCB up outside the scheme, your best option would be to find an insurer or broker, who will mirror your claims history from the scheme. This will ensure your not starting from scratch and depending on insurance company they could award 3 or 5 yrs NCB, which helps. After that first year you will have an extra NCB and can move to any insurance company.
It would be different if you were ditching the Enyak for a private car, but your not in this case.