Mountain Province Diamonds Inc. — Proxy Solicitation & Information Statement 2026

Apr 21, 2026

Date: April 21, 2026

Computershare

320 Bay Street, 14th Floor

Toronto ON M5H 4A6

www.computershare.com

To: All Canadian Securities Regulatory Authorities

AMENDED

Subject: MOUNTAIN PROVINCE DIAMONDS INC.

Dear Sir/Madam:

We advise of the following with respect to the upcoming Meeting of Security Holders for the subject Issuer:

Meeting Type : Annual General and Special Meeting
Record Date for Notice of Meeting : May 15, 2026
Record Date for Voting (if applicable) : May 15, 2026
Beneficial Ownership Determination Date : May 15, 2026
Meeting Date : June 30, 2026
Meeting Location (if available) : Virtual Meeting
Issuer sending proxy related materials directly to NOBO: Yes
Issuer paying for delivery to OBO: Yes

Notice and Access (NAA) Requirements:

NAA for Beneficial Holders : Yes
Beneficial Holders Stratification Criteria: Not Applicable
NAA for Registered Holders : Yes
Registered Holders Stratification Criteria: Not Applicable

Voting Security Details:

Description	CUSIP Number	ISIN
COMMON SHARES	62426E402	CA62426E4022

Sincerely,

Computershare

Agent for MOUNTAIN PROVINCE DIAMONDS INC.