Thanks ericadbr

Yes like you we are not VAT registered. And yes the 'solution' you mention is of no use to us. 

I just can't understand why quick books online doesn't allow for adding these 'allowances' into our annual accounts. That is after all what we have to do prior to submitting our tax returns..

There must be thousands of small business owners like us that use simplified expenses when preparing their annual trading figures. We're not a special case here !

TBH  as QB online does not feature a way of incorporating these allowances into our annual accounts I think that we will cancel our trial subscription pretty soon. I do like a lot of things about quickbooks online but it is of no use to me for making tax digital so I see see little point in paying for it.