Hi Goandeas,
You can check the reply timescales from HMRC via the online tool -
Check when you can expect a reply from HMRC - GOV.UK (www.gov.uk)
The timescales are applicable at the time and are subject to change.
Alternatively, you can also call the Centre for Non residents on the number below.
Number - 0300 200 3500
Overseas - 0044 191 203 7010
Open - Monday to Friday: 8am to 6pm Closed on Saturdays, Sundays and Bank Holidays.
Thank you.