So this might be an interesting one…
Currently in a redesign phase of Check-In and Baggage Systems owing to an increase of gates, etc. So I’d done about 60-90 mins of edits earlier - various things from deleting old rooms (both metaphorical and zoned) as well as many objects - all the whilst saving my current file. Including some of the tedious creating queues for Check-In desks (please hurry with the Copy+Paste command!).
Then the Bulldozer suddenly stopped doing anything… it wouldn’t grab, it wouldn’t click. Then I realised other things wouldn’t click. And then the W-A-D-X keys stopped responding for moving around the land. So I quit the game, quit the app, quit Steam and reloaded the whole thing including my latest Save File.
When I did that, it opened up this bizarre cross-version of my latest design. Majority of the elements I’d deleted during the 90 minutes had reappeared, but more strangely some of the new objects, only their shadows/placements remained - not the physical object 
I somehow have some objects (Check-In desks which I’m waiting to delete) on Floor -1 - some of the old desks remain but the entire terminal floor has vanished. It’s such a mismatch of missing things vs new things vs reinstated things I’d got rid of.
Any similar experiences?
So my “Phase 2 Glitch?” file name has now changed to “Phase 2…” 