Yeah I'm guessing it will forget that location after a while.
There's a "yeah, but..." I cleared out my "Frequent Locations" after checking out "why" one of the locations is the "place to go..." on my two iPhones - it's my mom's place, and each of my iPhones are on different cell networks - one's on ATTWS and the other's on VZW, with my mom's town literally on the fringe of network coverage. Going about 300 feet up the road there's no cell coverage whatsoever as that location is behind a hill (I know where the towers are as I helped locate them years ago) - and the room I crash in is behind the neighbor's metal carport. Sooooo...
My ATTWS phone has decent service, but it's always fading between LTE and 4G and sometimes EDGE with a "No Service" from time to time. The VZW phone doesn't work well except in one room - the county mom's in is in USCC territory but I'm never on "Extended" coverage there, opting for the weaker VZW tower in OR across the Columbia River.
What I noticed between the two iPhones' Locations was that my VZW phone (with the weaker, but constant, connection) had "3 visits" and my ATTWS phone had "26 visits", even though both were with me most of the time - my VZW phone is my main driver and goes with me everywhere, while the ATTWS phone generally sat at mom's place. I'm surmising that the "reconnection" of the phones to a network ultimately "logs" my location in the Privacy Location Services - I have had the ATTWS phone since 12/31 and I certainly haven't been to-and-from mom's place 25 times since then, I've been there 3 times as my VZW handset has registered.
Also, check out the postings in this thread that I commented in yesterday - there may be more to Apple's Maps backend than they're making public (
https://forums.macrumors.com/threads/apple-maps-home-business-listings.1954606/) - I think it's not a coincidence that both of these service updates went live on the pretty much the same day...
I've cleared out my phone's Frequent Locations (my two iPads as well - they're both cellular models), and we'll see what the next few days brings. I'm heading to the Seattle area Monday to buy a new-used Benz E550, so I'll be putting this feature to the test! Cheers!