VS 2019 (v16.8.6) was installed on Development Computer today (2021-03-02) as a test to workaround an issue with VS2017 whereby its performance had suddenly degraded to the point that it was interferring significantly with the development and testing of the AstroMain program. 
(Visual Studio 2017 became very slow to run a program in the debugger, and very slow/non-responsive for up to a minute after finishing a program in the debugger or after a fatal program exception etc.  Various attempted fixes / computer restarts failed to solve the issue)

Installation of the community version of the VS2019 was very straightforward and after moving a copy of the AstroMain project folder to the new '\Visual Studio 2019\Projects' area, the project was successfully opened ok in VS2019. Build/program execution/debugging seemed to have relatively normal performance.

Since it was an intention to move up to VS2019 at some stage and since the key AstroMain project seemed ok in VS2019  it was decided to move entirely over to the using the new Visual Studio version.

The following day (2021-03-03) other AstroSuite projects were imported to VS 2019 and had their version numbers changed to reflect the fact they had moved to new environment.    In particular AstroMove was modified to recognise the new project location (fortunately this was a single line change).   Programs were tested briefly for any critical issues, projects backed up and then installed onto the Observatory Computer and/or AllSky/Weather Computer as relevant.

Program		Previous Version	New Version
AstroAllSky		3.9.3	3.10
AstroLaunch		1.5.2	1.6
AstroGuard		1.5.1	1.6
AstroMain		3.37.7	3.38
AstroMove		1.6.2	1.7
AstroObsCam		1.4.6	1.5
AstroPlan		1.20.6	1.21
AstroProtect		1.5	1.6
AstroSN		1.4.1	1.5
AstroShCap		1.3.10	1.3.11
AstroVOE		1.6	1.7
AstroWeather		1.11	1.12

Update 2021-03-04
VS 2019 was later updated to v16.9.0 on 2021-03-04.
(Noticing that this version whilst stated to include bug fixes seem to have more bugs in it that than 16.8.6, or at least has bugs that have a greater impact on my work ! )

Update 2021-03-12
VS 2019 was later updated to v16.9.1 on 2021-03-12
(Hopefully this will fix some of the issues noticed in 16.9.0)

• Dome Software & Drivers were updated today (2021-03-04) using the 'Pulsar_Observatories_Package 1.0.38.0.exe'  installer
   
  (An update to Dome software was previously made on 2021-02-26 using the 'Pulsar_Observatories_Package 1.0.37.0' installer,
  but that install failed to put new software onto the Shutter Unit as expected)
   
• Dome Rotation Driver continued at v1.41.
  (Relay Settings, Time Settings and Azimuthal Position were preserved.  No recalibration required)
   
• Shutter software version jumped to v2.04~C on the second attempt
   (the first attempt having failed part way through, requiring removal/reinsertion of fuse and fresh attempt)
   
• Checking information from the Dome after the update showed unexpected battery information
  Battery Level 0%,  Voltage 4.1V, Temperature 24.9 degC 
  
  (this compare to values before the installlation of  97%, 15.0V, 5.8 degC, also the sounds coming from the Shutter Drive Unit when opening the shutter were also different with ~1 second of motor whinning before turning, then a bit more sluggish than normal ?)
  
  
  
• Discussed with Matthew Player (Electrical Engineer Support for Pulsar Observatories) who identified that the package had put on the wrong shutter software
  Instead of v2.04 (which is for the Mk2 version of the Shutter Drive Unit), the required new shutter version for my Mk 1 shutter was meant to be v1.23
  
  A custom manual installation of the shutter software is required.
  
  
• Update:  2021-03-04 pm
  
  'ES Updater' software has arrived by email in order to 'manually' install the new software to the Shutter.
  
  - Download and unzip file
  - Run “ES Updater.exe”
  - Select COM port of shutter unit   (COM 15 in my case)
  - Click “Select File” and select “Shutter_1_23.hex”
  - Click “Update”
  - Once updated remove fuse wait a minute then replace
  
  Ran the update as instructed but attempt to update to 1.23 failed with
  a Code 1010 (ST Erase Failed Other) and a message referring to a specific line.
  
  
  
  Fortunately it was possible to successfully rollback to 1.22
  
  
  
  So its back to the drawing board on 1.23....
  But at least back with 1.22 , the battery info is there again and the sounds from the shutter upon opening/closing are back to normal.
   
  
• Pictures of the bottom side of the Pulsar Dome Shutter Unit  illustrating difference between Mk1 and Mk2 Versions
  (Mk1 version has a fiddley fuse that has to be taken out / put back in during Shutter Software Installation)
  
  

2021-03-18 Update
A new software file (1.24), was received and installed to the Shutter Unit on 2021-03-18 but didn't resolve issue (details here).

Update 2021-03-31
Shutter was updated to a new 1.25 version on 2021-03-31 which finally resolved issues associated with the shutter falling asleep (details here).