Meal subsistence - working from home employees

Following the COVID lockdown we closed our permanent office and all employees became Home Workers. As part of this change to working conditions we changed our travel and subsistence policy to allow for travel and meals to be reimbursed if away from normal place of work (home). The rates we allow for meals is higher than I can find on the HMRC rate but this is because the majority of our meetings away from home are in London so we allow £15 for breakfast and £25 for lunch. I have 2 questions: 1. are we ok to reimburse the actual cost of meals for the higher amounts without incurring a tax liability for either us (employer) or the employee. 2. are there specific times for the reimbursement, e.g. for breakfast is there a time an employee must have left home before we can pay it. I think the HMRC guideline is before 6am but is this an actual rule, at the moment we allow breakfast if leaving home before 7am. Thanks

Hi,
We have attached a link to  guidance detailing allowable amounts and the time away from home for these rates to be applicable.
Anything outside this amount you will need to apply to HMRC for a bespoke rate:
EIM05231
Thankyou.