One more point to add - enabling/disabling flight mode within Ubuntu does not resolve the problem; but if I enable/disable on the laptop (there's a key sequence on this Entroware Apollo) then it gets Bluetooth working again. This might suggest that resetting the hardware is necessary to resolve which might indicate that the linux bluetooth support has crashed the silicon.
I've attached the journal.txt as requested.
One more point to add - enabling/disabling flight mode within Ubuntu does not resolve the problem; but if I enable/disable on the laptop (there's a key sequence on this Entroware Apollo) then it gets Bluetooth working again. This might suggest that resetting the hardware is necessary to resolve which might indicate that the linux bluetooth support has crashed the silicon.