Your eligibility to make lump sum withdrawals from your Ordinary Account (OA) will not be affected. This is because only the OA savings that cannot be withdrawn in a lump sum will be annuitised to provide you with higher CPF LIFE monthly payouts.
The purpose of your CPF savings is to provide you with a stream of retirement income. If you still have housing obligations after starting your monthly payouts, you can use your monthly payouts or monies in excess of your Full Retirement Sum after this transfer to meet your housing needs.