One of the changes in procedure in the new probate rules is that when you apply for an estate grant in British Columbia, you now have to give notice to beneficiaries and those who would be entitled to a share of the estate if the deceased had died without a will at least 21 days notice before filing for the estate grant, unless the court orders otherwise.
The requirements are set out in Rule 25-2. Rule 25-4(2) provides that the registrar must not issue an estate grant unless notice has been given in accordance with Rule 25-2.
You may prove delivery by swearing and filing an affidavit in Form P9. Interestingly, the form does not say when the notice was delivered.
The delivery requirements are considered in a recent decision of Master Caldwell in Davies Estate, 2014.
In that case the affidavit of notice was sworn four days before the application, and Master Caldwell refused to issue a grant. The applicant argued that because the deceased died before March 31, 2014, when the new Rules and the Wills, Estates and Succession Act came into effect, the old Estate Administration Act notice provisions applied, and the applicant did not need to give the 21 days advance notice.
Master Caldwell rejected the submission that the new rules did not apply. (As an aside, I note that although the new rules are in effect for all applications made on or after March 31, 2014, most of the substantive provisions of the Wills, Estates and Succession Act will only apply if the deceased died on or after March 31, and the substantive provisions of the Estate Administration Act, such as the distributions if the deceased died intestate, will still apply if the deceased died before that date.)
In order to assist the bar and others applying for estate grants, Master Caldwell issued reasons in which he discussed evidence that the 21 days have passed before the application for an estate grant is made as follows:
 Form P9 is the form which provides the registrar with evidence as to who received notice of the application and of what that notice consisted. Nowhere in the standard Form P9 is there specific reference to when notice was delivered, however, that does not reduce the duty on the registrar to be satisfied that proper 21 day notice has been provided.
 The absence of express evidence of the date of delivery is not fatal in itself. The Form P9 may well be silent in its body as to the date of delivery but may have been sworn 21 or more days before the application was submitted. In such case, as long as the list of enumerated persons correctly identifies the persons entitled to notice, the registrar may properly infer adequate notice and process the application for the estate grant. In situations where that Form P9 is sworn less than 21 days before the filing of the application the inference is not available and sufficient evidence as to the date of delivery must be provided in order that the registrar may be satisfied as to observance of and compliance with Rule 25-2. Where such evidence satisfies the registrar that proper 21 day notice was given before the application was filed, the matter may be processed based on the original application date; where the evidence fails to establish that 21 day notice was given before the application was filed the original application cannot be remediated and must be resubmitted following a proper 21 day notice period, established by proper evidence.