Ron,
I'm nowhere close to Essex county but put forth a possibility. Searching
TAFL between 420-421MHz which is likely where a system like this would
show up, I come up with 9 callsigns for groups of frequencies assigned to
Windsor Two-Way. UHF Fire in Canada does not usually use 450-470 as
in the US (there may be exceptions), but 410-430 instead.
callsigns CFT233/244/245, XKI962/967/970/977/983/995
Note that the standard split for 420-421 in Canada is -11.000MHz.
Several of these 420MHz groups show up as "pending" which means new
and not necessarily operational. These may turn out to be commercial-only,
who knows. They are all narrowband analog in groups so trunking is most
likely. If they're active, first would be to establish what kind of trunking is
being used (should not be difficult). If it weren't 8-10 hours drive from me
(at legal speeds...thinking about conserving gas

, I'd be checking it out.
Searching these groups may seem tedious but for lack of any other info, is
my best guess.
Dave