If you are a beneficiary but not an executor then you don’t have an automatic right to demand information from the solicitor instructed by the executor (unless the solicitor is itself the executor). You should really be contacting the executor and asking them for a progress update.
For context: my FIL died last year, the tax return was filed 8 months after the death, the probate application was filed 6 weeks after that, and the grant of probate was 3 weeks after the probate application was filed. The beneficiaries were paid just under a year after his death. After a year the beneficiaries can claim interest, but until a year is up I would not expect the whole process from death to payment out to take much less than a year.
First of all, the assets have to be identified and valued, and both of those may take time. You say that the house had been sold but you don’t mention whether there were other assets such as shareholdings, jewellery etc.
Second, if the estate is close to or over the inheritance tax threshold or if it would be but tax relief is being claimed, an inheritance tax return has to be submitted. That (a) has to be paid before the grant of probate and (b) the tax return has to be sent to HMRC before the probate application is filed so that HMRC can approve it and forward it to the probate office so that it can be married up with the application when it comes. If you send the application off before the tax return is there, the application will be “stopped” ie put to the bottom of the pile pending resolution of the problem, which can lead to delays of up to 16 weeks. It is recommended that you wait at least 5 working weeks after filing the tax return before filing the application so that HMRC has had time to approve the return and send it to the probate office.
Once the application is in, it should only take 3-5 weeks for an electronic application, though if there are any complexities this can again result in it being stopped.
When probate is granted it can still take a lengthy period for money to be released if they are investments. I did a lot myself for FIL’s estate after grant of probate and you have to find out what info they need (eg certified or original ID docs of the executors which are often needed as well as the grant itself), fill in the forms, send off the info, and it can take 28 days or longer after that for investments to be liquidated and sent to solicitors.