Hello @MartinLangmaid,
Back in my days in another industry, we use to monitor the number of satellites the GPS system was listening to for timing accuracy verification, mind you the GPS timing systems we used were worth a lot of money and had a lot of bells and whistles (features), these systems run mission critical environments with redundancy on top of redundancy (imagine High Availability with another layer of High Availability on-top).
So @jo.campus, is this why you would need this? if so would you consider perusing the mission critical timing systems used in industries like defence and if a little less critical, the broadcasting industry (look up “Television Station Reference clock generators”), my favourite is the Evertz 5601MSC 5601MSC - Master SPG/Master Clock System.
The chipsets in the MAX units I would expect are not designed for that level of monitoring and accuracy. That they do as well with there current tasks is great.
I still would like to use the MAX as and NTP time server (Having unit be an NTP time server would be helpful - #15 by mldowling), though the need for monitoring the GPS satellites being listen to is something that we would like to understand more of the why on too.
Another area that maybe knowing the number of GPS Satellites being listen to would be useful for is to test your GPS antenna, is this along the lines of what you are thinking?
Happy to Help,
Marcus 