Can I use EIM66205 Benchmark scale payments for allowable expenses (subsistance)

EIM66205 is for Lorry Drivers and for Employees, I am neither. I am a self employed same day courier (light haulage) driving a small van. I travel anywhere in the country, at short notice to deliver items and often sleep in the back of my van (or occasionally in cheap hotels). Each day I have no idea where I am going, nor where I will end up. I follow the work. Although I'm in a small van, the way I operate is largely similar to the way national long distance lorry drivers operate. I am definitely an "Itinerent worker". This means I can claim reasonable subsitstance and accommodation as allowable expenses. To date I have been doing this with actual costs. Having come across the "Benchmark scale rate payments" of EIM66205, I would much rather use these payments as a form of simplified subsistance accounting. As a non lorry driver, and as a non employee, am I allowed to do this? If I am not, what other options might there be available to me? To me, it makes sense to be allowed to use these simplified scale rate payments.

Hi,
No as this is not your employment.
Please refer to Expenses if you're self-employed
Thank you.