I, too, am a Lost Canadian.   My family lost ours in 2004 after being in Canada with citizenship since 1946 (my dad came in 1925 as a child but went back to serve in WWII, so we were born in Britain). My brother served in the Canadian Navy and a Police force.   I worked full time for over 50 years, paid all taxes,  had SIN cards and all.   We got no notice or hearing,  just found out when my brother applied for a passport (never needed in the Navy) and was told our citizenship had been stripped.    I have not been able to travel out of country since.  There were thousands of War Brides and children in this mess.
 I get CPP and OAS which are based on residency but so many organizations require citizenship, even for volunteers.
Our children are all Canadian citizens, but also entitled to British because of our birth there, so they are vulnerable to revocation also.    I am not sure what the legal answer would be, but surely there must be a better way for Canadian citizenship.