Thanks for your question. I will try to help.
Firstly, you should ask your solicitor what the consequences of not completing on the contractual completion date will be. The contract which you exchanged will govern that.
Usually a contract will allow the seller to serve a notice to complete on you (via your solicitor). This notice would usually give you 10 working days to complete. This would allow you further time within which to arrange a new mortgage offer and then complete. So, if the contract provides for this then you would be able to complete within the time period specified in the notice to complete when it is eventually served on you by the seller’s solicitors. However, there will likely be some extra legal fees of the seller’s solicitor to pay, together with interest on the balance of purchase monies. However, these should not be particularly large.
As to the expiry of the mortgage offer, I would normally expect the solicitor to advise you of the expiry date of your mortgage at some point prior to exchange and to let you know that if completion is to occur after the expiry date that you should arrange a new mortgage to replace the old one. If they have done this in correspondence to you then you would likely not have a claim against the solicitor. If they have not done this then you may potentially have a claim against them if you are not subsequently able to complete.
In the first instance, I would focus your efforts on getting the new mortgage offer, but also to contact your solicitor to get them to assure you that once the mortgage offer comes in that you will be able to complete without any further issues. I would ask them to reassure you that you have signed all the necessary documents (ie. Land Registry Transfer) they require to complete apart from the mortgage deed (which will be sent to the solicitor with the mortgage offer when it comes). I would also get them to check the validity of your searches, because it is possible that they may have expired by the time completion comes since they must be less than 6 months old at the time of completion. If they have expired then you should ask your solicitor whether search indemnity insurance is available in order to validate the old searches for the purpose of your new mortgage.
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