[1] We note at the outset that judgment in this case was entered out of court and out of district from the 24 January 1983 term of Dare County Superior Court. Such an entry of judgment is proper only where permitted by statute, or, as here, where the parties consent. Utilities Commission v. State, 243 N.C. 12, 89 S.E. 2d 727 (1955), reh. denied, 243 N.C. 685, 91 S.E. 2d 899 (1956).
Defendant contends that the trial court erred in ordering specific performance of the contract, because it had either lapsed or been rescinded as of 26 September 1981, when plaintiff attempted to convey the executed note and deed of trust to defendant. Plaintiff contends that the time for performance of the contract was extended on 29 January and 4 August and a binding agreement existed on 26 September 1981.
To determine whether a valid contract existed on 26 September 1981, we must examine the legal effect of the events occurring between August 1980 and September 1981. Under the agreement executed on 18 August, closing in the land sale was to be held on 9 January 1981. The sale was conditioned, however, on *434defendant’s ability to obtain a divorce from his wife or her consent to a deed by the closing date. This provision constitutes a condition precedent to the parties’ obligation to perform under the contract. “Conditions precedent . . . are those facts and events, occurring subsequently to the making of a valid contract, that must exist or occur before there is a right to immediate performance, before there is a breach of contract duty . . .” 3A Corbin on Contracts § 628 (1960 & 1971 Supp.), Tire Co. v. Morefield, 35 N.C. App. 385, 241 S.E. 2d 353 (1978).1 It is clear therefore that neither party was obligated to perform under the contract unless the condition precedent was met by the closing date.
[2] It is undisputed that as of 9 January 1981 the condition precedent had not occurred and the parties were not required to perform, but it does not follow that the contract expired immediately thereafter. As a general rule, a contract for the sale of land remains valid and binding for a reasonable time after the date set for closing, Scarborough v. Adams, 264 N.C. 631, 142 S.E. 2d 608 (1965), unless the contract specifies an expiration date, or clearly states that time is of the essence, see Douglass v. Brooks, 242 N.C. 178, 87 S.E. 2d 258 (1955). There is no showing, nor do the parties contend that time was of the essence or that a specific expiration date was set in the case at bar. What constitutes a “reasonable time” for performance depends upon the nature of the contract, the purpose and conduct of the parties and all other relevant circumstances, United States v. 969.46 Acres of Land, Chatham Cty., N.C., 386 F. Supp. 793 (M.D.N.C. 1974), aff’d, 535 F. 2d 1251 (4th Cir. 1976) (defining reasonable time to exercise option contract). See also Rodin v. Merritt, 48 N.C. App. 64, 268 S.E. 2d 539, disc. rev. denied, 301 N.C. 402, 274 S.E. 2d 226 (1980).
[3] The issue of whether a reasonable time has elapsed normally presents a mixed question of fact and law to be decided by the trier of fact, Colt v. Kimball, 190 N.C. 169, 129 S.E. 406 (1925). Where the facts of the case are simple, undisputed and can lead only to one conclusion, however, the issue presented becomes one of law which may be decided by the trial judge. Id. After a *435reasonable time has elapsed, the contract is terminable at will by either party, upon reasonable notice to the other, Fulghum v. Selma, 238 N.C. 100, 76 S.E. 2d 368 (1953).
The problem before us thus becomes to determine what date the parties set for performance, as that is the date from which they had a reasonable time in which to perform under the contract.
[4] We turn first to the agreement executed by the parties on 29 January 1981 purporting to extend the closing date to 10 March 1981. Contract terms may be validly modified where the modification has the consent of all parties and is supported by adequate consideration. Corbin v. Langdon, 23 N.C. App. 21, 208 S.E. 2d 251 (1974). Contracts for the sale of land must be in writing, N.C. Gen. Stat. § 22-2 (1965), and modifications of a land sale contract must also be written to be valid, see Westmoreland v. Lowe, 225 N.C. 553, 35 S.E. 2d 613 (1945). The undisputed facts in the case at bar show that the agreement of 29 January 1981 was in writing and was mutually agreed upon by the parties. Although the cases conflict somewhat, there is authority to support our position that an exchange of written, mutual promises to extend the duration of a contract for the sale of land is binding upon the parties without further recitation of consideration, Childress v. Trading Post, 247 N.C. 150, 100 S.E. 2d 391 (1957), 17 Am. Jur. 2d Contracts § 461 (1964), but see Tile and Marble Co. v. Construction Co., 16 N.C. App. 740, 193 S.E. 2d 338 (1972). We hold, therefore, that the agreement executed by the parties on 29 January 1981 validly modified the contract and set 10 March 1981 as the new closing date.
Plaintiff contends, however, that defendant further modified the contract by virtue of his conversations with plaintiff between 10 March and 4 August 1981, indicating his continuing willingness to convey the land as soon as his divorce became final. The facts, as found by the trial court, show that these communications were oral and informal. There is no finding that either party intended to modify the terms of the existing contract, or that the parties exchanged mutual promises or other consideration. Under these circumstances, we hold that defendant’s unilateral, oral statements were insufficient to constitute a valid modification of the *436contract closing date.2 The final, binding agreement between the parties thus provided for closing on 10 March 1981 and the parties had a reasonable time thereafter to fulfill their obligations under the contract.
[5] Nevertheless, defendant’s conversations with plaintiff constitute some evidence of the parties’ intent as to time for performance and are thus relevant to the question whether defendant acted within a reasonable time after the March closing date. Although the facts in the case before us are undisputed and relatively simple, they do not inevitably lead to a single conclusion concerning whether a reasonable time had elapsed when defendant attempted to terminate the contract. The question is therefore one for the trier of fact, considering all the circumstances of the case, Colt v. Kimball, supra. The trial court made findings of fact concerning the passage of time between the March closing date and the time of defendant’s termination, but made no adequate findings of fact or conclusions of law concerning whether a reasonable time had elapsed. Because the trial court failed to apply the proper legal standard to the facts in reaching its judgment, the case must be remanded for further proceedings consistent with this opinion.
[6] We turn now to plaintiffs cross appeal for $40,400.00 in special damages incurred in reliance upon the land sale contract. In certain cases, special damages may be awarded in addition to specific performance if necessary to place a purchaser in the same position he or she would have occupied if no breach occurred. See Winders v. Hill, 141 N.C. 694, 54 S.E. 440 (1906), 71 Am. Jur. 2d Damages § 216 (1973). In the case before us, plaintiff incurred certain expenses as a result of her preparations to develop the land subject to the sales contract. While these expenses were incurred in reliance upon the contract, they are not attributable to defend*437ant’s breach, if any. These are expenses that plaintiff would have incurred had defendant conveyed his land to plaintiff. To award plaintiff specific performance as well as compensation for her development costs would be to place her in a better position than she would have occupied had defendant conveyed. We hold, therefore, that even if the trier of fact determines on remand that defendant breached the contract, plaintiffs claim for special damages must be denied.
Affirmed in part and remanded.
Judge Johnson concurs.
Judge Becton dissents.