Русско-англо-русский юридический словарь

You certainly do not have to agree to change the completion date to suit your buyers, but if you do, it is very important you tell your solicitor so he can then vary the contract formally.

Ideally, your solicitor should prepare a supplemental agreement changing the completion date and your buyers should pay your solicitor's costs for drafting it. Both you and the buyers will need to sign the supplemental agreement.

In the absence of an express or fixed time established by the parties to an agreement or contract (especially one that falls under the purview of the Uniform Commercial Code [UCC]), any time which is not manifestly unreasonable under the circumstances. For example, if a contract does not fix a specific time for performance, the law will infer (and impose) a reasonable time for such performance. This is defined as that amount of time which is fairly necessary, conveniently, to do what the contract requires to be done, as soon as circumstances permit. The term "reasonable time" has other (related) applications: UCC 2-206(2) requires that acceptance of an offer be made within a "reasonable time" if no time is specified. (West's Encyclopedia of American Law, edition 2)

A business day is considered every official working day of the week. Another common term is working day. Typically, these are the days between and including Monday to Friday and do not include public holidays and weekends. (Wikipedia)

The High Court has provided a useful reminder on the law of penalties, confirming that payments made on the early termination of a contract (where the reason for termination was not a breach of contract), do not amount to a penalty clause. (Website of Myerson)