VAT manual adjustment

First VAT Return filed via MTD to HMRC which includes manual adjustments. VAT Return filed on the basis of cash accounting and a flat rate of 10.5%.

Two adjustments made;

  1. Discount given by HMRC for first year registration for the Flat Rate Scheme
  2. Payments received for invoices that were invoiced prior to VAT registration

The two manual adjustments were showing on the Balance Sheet as Current Liabilities (2204) Manual Adjustments.but both journaled to (4999) Flat Rate VAT Sales Adjustment which seems appropriate for the discount received but not for the pre-registration Sales Invoice payments received as the result is an increase in the turnover figure.

What is the appropriate nominal ledger account to journal pre-registration Sales Invoice payments?