If you read through my previous post on this thread, you might find the answer you are looking for, as I have no idea to what your point is.

Your letter should read something like -
To: HMRC
I would like clarification on a certain issue.
As you are no doubt aware, I operate a window cleaning business and operate locally (and/or nationally).
Please could you clarify the situation concerning 'meal allowances' or 'food' generally while I am at work.
I have read some information that leads me to believe I can claim a 'daily allowance' for food for each day I am working.
Please could you clarify this point and also state what legislation/law/regulation you are using to support this advice.
Hugs and kisses..
Ewan.
Send something like that, and let me know what they say.
Reading your posts, you have possibly misinterpreted some advice concerning another field or industry. Each has its own unique (and peculiar) tax allowances.
I would stake my reputation on the answer being -
NOT Allowed for local window cleaning (if you go home at the end of the day). HMRC will back this up with some evidence and case history and inform you by letter of their findings.
If you have already done this, I say again - please let me know the
EXACT wording of your letter to HMRC and their reply.