Former First Kernow & Western Greyhound Optare Solo YJ55 YGN (53406) along with YJ05 XNV (53205) are now with Trustybus, Essex according to the Fleet news section in the latest Buses Magazine. They were disposed of by FK to Ensign in April.
Indeed they have:

Green Goblet: Trustybus (ex First South West) Optare Solo M880 YJ55YGN Stansted Road Stansted Mountfitchet 11/05/20
Disclaimer: Precisely zero walking humans encountered during this brief 20 minute dose of walking exercise and the coincided photo stop. With the ongoing global situation and a discouragement on using public transport except for key and essential personnel, much of the transportation system in...
That YJ55YGN is a certain little solo with an unfortunate (or cursed) history, having previously been K50WGH - One of the Solos bought down to Cornwall during the Smith and Bishop takeover of Western Greyhound from the Velvet fleet (and before Velvet was left to die off). I believe it was refurbished at some considerable expense and fitted with Wifi, right before Greyhound was finally closed down, and was their last vehicle to run on the road as well. It also happened to be the vehicle that Mr Bishop once proudly proclaimed would be "representing the future of Western Greyhound"...