Part 4, Division 6 of the Wills, Estates and Succession Act allows a spouse or child of a deceased will maker to apply to court to vary a will if the will maker did not make adequate provision for them. If the Court finds that the will-maker did not make adequate provision for his or her spouse or children, as the case may be, the Court may vary the will to make such provision as the Court thinks “adequate, just and equitable in the circumstances.”
Subject to the right of an appeal, once the Supreme Court of British Columbia makes an order varying a will (or refusing to vary the will), then that is usually the end of the matter. The will-maker’s personal representative carries out the will as varied.
But there are limited circumstances where a Court could vary the Court’s variation of the will. Section 71 of the Wills, Estates and Succession Act provides:
Court may cancel or vary order
71 If the court has ordered periodic payments, or that a lump sum be invested for the benefit of a person, the court may
(a) inquire whether, at any subsequent date, changes in the circumstances of the person in whose favour the order was made have resulted, in whole or in part, in the person's entitlement to adequate provision separate from the order, and
(b) cancel, vary or suspend its order, or make another order.
Despite some changes in the wording, this provision is substantially similar to section 14 in the Wills Variation Act, which it replaced when the Wills, Estates and Succession Act came into place.
The section would not apply to a variation in which the person on whose behalf the will is varied is awarded a specific sum of money, or an asset, or a percentage of the estate, which are the more common types of awards made nowadays. It would apply in more limited circumstances, such as an order setting aside a sum of money or percentage of the estate, out of which payments are to be made to the claimant, with giving the claimant an entitlement to the whole of the fund. For example, the court could set aside $200,000 to be invested, with $2000 per month paid out of that fund to the claimant, and with anything left in the fund on the claimant’s death divided among the other beneficiaries.
I have not found any court cases that have applied section 71 (or the earlier similar provisions in the Wills Variation Act, and Testator's Family Maintenance Act).
I have difficulty conceiving when it would be applied under the modern principles applied to wills variation cases. The provision strikes me as a holdover from the days when the legislation was seen more as a vehicle for ensuring that a husband and father (in the 1920s, it was usually a husband and father) did not leave his wife and children destitute. It was more common for the courts to make orders that provided for monthly payments to meet a spouse’s or child’s needs. The current section 71 appears to be intended to cover a situation where those needs are met by a different source, perhaps through employment, recovery from an illness, or another inheritance.
Under the more modern approach, as articulated by the Supreme Court of Canada in Tataryn v. Tataryn  2 S.C.R. 807, the court considers whether the will maker satisfied his or her legal and moral obligations to the claimant. If not, then the court varies the will to satisfy those legal and moral obligations. The awards will often be greater than that required to satisfy the claimant's basic financial needs, sometimes significantly so including awards in the millions.
The court considers whether adequate provision has been made to the spouse and children at the time of death the will-maker’s death, although the Court may consider a substantial change in circumstances between the date of death and trial when making the variation (Landy v. Landy Estate, (1991) 60 B.C.L.R (2d) 282 (CA)).
The variation satisfies the will-maker’s obligations to the claimant, and logically the successful claimant has established a corresponding entitlement.
If the court finds that the will-maker did not make adequate provision for a spouse or children, and the court varies the will, then I have difficulty conceiving how a change in the claimant’s circumstances after the trial judgment should affect his or her entitlement, irrespective of the structure of the variation ordered by the court (outright share of an estate, or periodic payments). Either the will-maker met his or her legal and moral obligations at the time of death, or he or she did not. If not, why should an improvement in his or her spouse or children’s circumstances after trial change that?