Self assessment return including supplementary page SA109

Last year I filled in a tax return including supplementary page SA109. I subsequently received a letter in France stating that 'Things are changing from this year - we are asking you to file your return online'. The letter said that I should fill in my return online. Having completed the online form, I am not able to fill in the self-assessment residence remittance basis (SA109) form using the online system. I have missed the date for the paper submission, but would have completed it by the due date if I was aware that it was not possible to complete online. What is recommended in this situation? Should I fill in the online form as best I can and send the other relevant forms on paper, or just complete the full paper form and submit it?

Hi James,
You can purchase 3rd party software to file the whole return or send the whole return in paper form.
If you choose paper, please include a letter of appeal against any late filing penalties.
Thank you,