How long are HMTRC taking to respond at the moment?

I received a letter in May saying that I would hear within 8 weeks re income tax due prior to my late mother's death. 15 weeks have now elapsed - no reply. Also, I wrote in early July with my calculation of tax due in the Administration period between death and accounts being closed. No reply. How long is HMRC taking at the moment? Should I wait or ring to query? I assume HMRC would like the payments!

Hi Fenlli,
We are sorry for any delay you have experienced in waiting for a reply to your query.
If you have not received a reply, please contact us by webchat or phone here:
https://www.gov.uk/government/organisations/hm-revenue-customs/contact/income-tax-enquiries-for-individuals-pensioners-and-employees
Income Tax: general enquiries.
Thank you.