GHCUP fails to retrieve current .yaml file

On a host behind a firewall, the firs attempt to retrieve ghcup-0.0.6.yaml that ghcup does under the hood on ghcup list, fails:

$ ghcup list
[ Info  ] downloading: https://www.haskell.org/ghcup/data/ghcup-0.0.6.yaml as file /Users/ur20980/.ghcup/cache/ghcup-0.0.6.yaml
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:--  0:00:02 --:--:--     0
[ Warn  ] Could not get download info, trying cached version (this may not be recent!)
[ Error ] JSON decoding failed with: YAML exception:
[ ...   ] Yaml file not found: /Users/ur20980/.ghcup/cache/ghcup-0.0.6.yaml
[ ...   ] Consider removing "/Users/ur20980/.ghcup/cache/ghcup-0.0.6.yaml" manually.
$ 

Subsequent invocation succeeds:

$ ghcup list
[ Info  ] downloading: https://www.haskell.org/ghcup/data/ghcup-0.0.6.yaml as file /Users/ur20980/.ghcup/cache/ghcup-0.0.6.yaml
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  112k  100  112k    0     0   129k      0 --:--:-- --:--:-- --:--:--  131k
   Tool  Version        Tags                      Notes      
✗  ghc   7.10.3         base-4.8.2.0                         
.  .  .  .  .
✗  ghc   8.10.4         base-4.14.1.0             hls-powered
✓  ghc   8.10.5         base-4.14.2.0             hls-powered
✓  ghc   8.10.6         recommended,base-4.14.3.0            
✔✔ ghc   9.0.1          latest,base-4.15.0.0      hls-powered
✗  ghc   9.2.0.20210422 prerelease,base-4.16.0.0             
✗  cabal 2.4.1.0                                             
✗  cabal 3.0.0.0                                             
✗  cabal 3.2.0.0                                             
✔✔ cabal 3.4.0.0        latest,recommended                   
✗  hls   1.1.0                                               
✗  hls   1.2.0                                               
✔✔ hls   1.3.0          latest,recommended                   
✗  stack 2.5.1                                               
✗  stack 2.7.1                                               
✔✔ stack 2.7.3          latest,recommended                   
✔✔ ghcup 0.1.16.2       latest,recommended                   
$ 

This is not a show-stopper, even though it breaks some scripts, but still is pretty annoying. Is there anything you could do to determine the cause and alleviate the problem? Thanks!