Looks like I've had another day of pointlessly waiting in for a delivery - the tracking says:
In Transit
Scheduled delivery Monday 17/08/2020
but the shipment progress hasn't updated to "Out for delivery" today - its still on the "In Transit" status which was updated at 6pm on Friday.
I messaged the shop this morning with my concerns that the tracking info was vague and contradictory, asking whether they could chase up UPS for info, but only got a reply telling me to let them know if it doesn't come today. I then tried to phone UPS, but after having a robochat and taking the option to speak to an agent I was told that option was not possible. So I've stayed in waiting just in case it comes, although it looks like today isn't going to be the day.
Grrrrrrrrrrr!