Adverse Possession

Good evening
An Adverse Possession claim has been submitted to yourselves, it is regarding a small parcel of land within the the garden. It measures less than 2 metres by 1 metre within a fairly large garden. I don't understand how this has happened. I have owned the land and property since the early 1990s. Our Solicitor has put in an Adverse Request on the expedited service just 2/3 days ago. What are current timeframes and an estimation of how long this will take? We are currently 5 months in to the sale process and are obviously concerned about this unforeseen delay. 

any support would be greatly appreciated.

Good Morning John - expedition gets the case to the processing start line asap and usually within 10 days.
Everything then depends on it being in order and there can be 3 key stages involved 
The first is consideration of the claimed facts - are they sufficient in law to warrant the claim being registered (2-3 weeks)
The second is a site visit, if needed, to survey the site and ensure the reality matches the facts (2 weeks)
The third involves wider checks with neighbouring/affected landowners to see if they object (or consent) to the claim for any reason (3 weeks)
Stages 2 and 3 can't be expedited as we are reliant on Ordnance Survey and third parties respectively. But each stage follows on from the next so is reliant on the previous one completing/deciding what happens next
The (weeks) indicators are just that - very rough indicators of timescales involved if stages 2 and 3 are needed and each goes to plan as you would hope for
Your solicitor will be contacted if something more is needed or if the claim is not in order. They and you as the registered owner will also be contacted if a survey is required.
They are the ones to provide support during the process but if you need to post again at any time do ensure you have obtained the title numbers and our ABR (case) reference from them to assist you

Thank you for you very quick response. 
It is strange as it is towards the middle of the garden and is a very small parcel of land in comparison to the size of the garden, measuring less than 2 metres and less than 1 metre. It is away from the boundary and there is no right of way for anyone over the property to get to this land. And there wouldn't be any other affected properties. I have owned the property for over 40 years and the land for over 30 years.  

It is also flagging as unregistered. Does this mean the process will be more straightforward and could an indemnity be taken out on this to get the sale through?

John - all noted and appreciated re the land. The process is always straightforward providing everything is done correctly starting with the facts on which the claim is based.
Whether an indemnity would work for the buyer invariably comes down to whether they are buying with a mortgage (the lender may say No) and something for their conveyancer to say Y or N to of course.
But a Q for your conveyancer to answer for you as presumably that's already been discussed with the buyer/conveyancer/lender
 

Really grateful for your responses, thank you. Fingers crossed this moves forward as speedily as possible,