@whaywood1 Hope you're doing well.
Regarding your query on the viewing and filtering the transaction for a period for tax purpose.
Your accountant can use the report "Transaction list by date" ( snippet given below) which provide list of all transaction within the date range provided by you.
Apart from adjusting the date range , the report allows to customise the customise the columns to be shown on report ( You might need the vendor name, tax code, taxable amount, ship via details to work on the VAT return).
Hope this helps , Do let me know if you have any questions to me.
Pai
Bookkeeper.