I am sure that you have had communications with UNUM regarding the claim. has the claim been accepted, have they given any reason for the delay?
If you feel that the speed of the processing is too slow and you have had no communications regarding the claim then you should place a formal complaint and state the position that you are in.
I agree that while certain elements of a cliam may need to be verified the provider also has a respopnsibility to process the claim as quickly as possible to ensure that they are not placed under any further hardship through loss of income than is reasonably possible.
I would like to think that this has happened through an oversight but constant communication should be passed from the provider to yourself as to the claim process.
If you get no joy from the complaint (they can take up to 8 weeks to respond) then the case should be passed onto the ombudsman as 8 months to process a claim is unfair to yourself unless you fully understand the reason why the delay is taking place.
Don't go directly to the ombudsman, they will only refer it back to UNUM and they will then have a further 8 weeks to respond again