How do I give some people limited time access to Mapshare

As far as I'm aware, changing passwords is the only mechanism available.

Yeah, that’s the only thing I’ve seen so far. It may be that Garmin just doesn’t offer that facility, in which case the easiest thing would be to pull the data to another location, from which users can control for themselves who has access, but it also sounds like Garmin only gives API access to business accounts, so it feels like they’re deliberately making it hard…

I don't think they're deliberately making it hard. My perspective is that they bought a company called DeLorme in 2016, and it was DeLorme who developed the inReach technology. Garmin has not made any inReach improvements since the purchase.

Link management is not going to work. you only have one MapShare page. All links point to the same place.

Password changes are the most flexible way to manage this.

You CAN set up your MapShare page to show only data after a particular date. This applies to track points. Not sure about messages. Definitely does not apply to marked waypoints.

"Garmin has not made any inReach improvements since the purchase"

This is incorrect.  Garmin has made many changes since 2016 in hardware & software, although some are debatably not improvements.

New iR devices which are full members of the Garmin ecosystem. For example, the 66i and the 7x0i have all the features of normal Garmin handhelds. They use Garmin maps, have geocaching features, etc.

In the debatable category, there are the Mini 1 and 2. Lousy GPS reception, one foot in the Garmin ecosystem and one in the legacy DeLorme universe. 

In the "wow, that's a bad idea" category, there is the proliferation of mobile apps - Earthmate, Explore, Garmin Connect Mobile - and the fact that you have to "just know" which app will (or will not) work with whatever device you have.

My original comment was about no new inReach improvements, to which Bob_qx wrote I was incorrect.  There have been no new inReach improvements, even with newer devices.  The messaging, Mapshare, and other inReach functionality have remained pretty much unchanged.

I wasn't referring to GPS functionality.

iR messaging uses what is known as Iridium short messages. Message length is limited by the mechanism. The system has always supported iR to iR messages, messages to (and replies from) phones via SMS, and messages to (and indirect replies from) email. In addition, there are interfaces to social media (not that they are frequently used). Not sure what is missing from a functional standpoint - do you have something specific in mind?

Believe it or not, the explore.garmin.com website and the associated MapShare page have changed substantially over the years. In particular, the introduction of the concept of "collections" was a huge change. That said, not everyone agrees that it was an improvement. There have been improvements in rendering of tracks on the map.

Unfortunately, explore.garmin.com and MapShare have been somewhat unstable, especially when large changes are made. 

I am not stating that anything is missing. I am stating that the current inReach functionality in the Mini 2 is essentially the same as the inReach functionality when Garmin purchased DeLorme.

"Collections" and rendering of tracks are associated with GPS functionality, not inReach.