Timeout when adding dependencies to project

Dub cannot find dependencies at https://code.dlang.org this is the main registry.
Works fine using the snap package 'dub'. Issue doesn't appear on 18.04 using a different version of dub. Version of dub downloaded from https://dlang.org/ works. I expect it to resolve dependencies and build my project.

Output of lsb_release -rd
Description: Ubuntu 20.04 LTS
Release: 20.04

Output of apt-cache policy dub
dub:
  Installed: 1.19.0-1build2
  Candidate: 1.19.0-1build2
  Version table:
 *** 1.19.0-1build2 500
        500 http://archive.ubuntu.com/ubuntu focal/universe amd64 Packages
        100 /var/lib/dpkg/status

Output of 'dub' when running 'dub build --verbose' using latest bindbc-sdl v0.16.0 (https://code.dlang.org/packages/bindbc-sdl) at time of writing:
Using dub registry url 'https://code.dlang.org/'
Refreshing local packages (refresh existing: true)...
Looking for local package map at /var/lib/dub/packages/local-packages.json
Looking for local package map at /home/ubuntu/.dub/packages/local-packages.json
Looking for local package map at /home/ubuntu/testing/.dub/packages/local-packages.json
Note: Failed to determine version of package testing at .. Assuming ~master.
Refreshing local packages (refresh existing: false)...
Looking for local package map at /var/lib/dub/packages/local-packages.json
Looking for local package map at /home/ubuntu/.dub/packages/local-packages.json
Looking for local package map at /home/ubuntu/testing/.dub/packages/local-packages.json
  Version selection for dependency bindbc-sdl (bindbc-sdl) of testing is missing.
  Missing dependency bindbc-sdl ~>0.16.0 of testing
Refreshing local packages (refresh existing: false)...
Looking for local package map at /var/lib/dub/packages/local-packages.json
Looking for local package map at /home/ubuntu/.dub/packages/local-packages.json
Looking for local package map at /home/ubuntu/testing/.dub/packages/local-packages.json
  Version selection for dependency bindbc-sdl (bindbc-sdl) of testing is missing.
  Missing dependency bindbc-sdl ~>0.16.0 of testing
Checking for missing dependencies.
Search for versions of bindbc-sdl (1 package suppliers)
Package supplier registry at https://code.dlang.org/ failed with 'HTTP request returned status code 0 ()', trying fallbacks.
Fallback package supplier registry at https://code-mirror.dlang.io/ failed with 'Failed to download https://code-mirror.dlang.io/api/packages/infos?packages=%5B%22bindbc-sdl%22%5D&include_dependencies=true&minimize=true'.
Fallback registry at https://dub-registry.herokuapp.com/ succeeded
Package supplier registry at https://code.dlang.org/ failed with 'HTTP request returned status code 0 ()', trying fallbacks.
Fallback registry at https://dub-registry.herokuapp.com/ succeeded
Package supplier registry at https://code.dlang.org/ failed with 'HTTP request returned status code 0 ()', trying fallbacks.
Fallback registry at https://dub-registry.herokuapp.com/ succeeded
Package supplier registry at https://code.dlang.org/ failed with 'HTTP request returned status code 0 ()', trying fallbacks.
Fallback registry at https://dub-registry.herokuapp.com/ succeeded
Package supplier registry at https://code.dlang.org/ failed with 'HTTP request returned status code 0 ()', trying fallbacks.
Fallback registry at https://dub-registry.herokuapp.com/ succeeded
Package supplier registry at https://code.dlang.org/ failed with 'HTTP request returned status code 0 ()', trying fallbacks.
Fallback registry at https://dub-registry.herokuapp.com/ succeeded
Package supplier registry at https://code.dlang.org/ failed with 'HTTP request returned status code 0 ()', trying fallbacks.
Fallback registry at https://dub-registry.herokuapp.com/ succeeded
Package supplier registry at https://code.dlang.org/ failed with 'HTTP request returned status code 0 ()', trying fallbacks.
Fallback registry at https://dub-registry.herokuapp.com/ succeeded
Package supplier registry at https://code.dlang.org/ failed with 'HTTP request returned status code 0 ()', trying fallbacks.
Fallback registry at https://dub-registry.herokuapp.com/ succeeded
Package supplier registry at https://code.dlang.org/ failed with 'HTTP request returned status code 0 ()', trying fallbacks.
Fallback registry at https://dub-registry.herokuapp.com/ succeeded
Package supplier registry at https://code.dlang.org/ failed with 'HTTP request returned status code 0 ()', trying fallbacks.
Fallback registry at https://dub-registry.herokuapp.com/ succeeded
Package supplier registry at https://code.dlang.org/ failed with 'HTTP request returned status code 0 ()', trying fallbacks.
Fallback registry at https://dub-registry.herokuapp.com/ succeeded
Return for bindbc-sdl: [0.7.0, 0.6.1, 0.6.0, 0.5.1, 0.5.0, 0.4.1, 0.4.0, 0.3.0, 0.2.0, 0.1.0, ~master]
Unresolvable dependencies to package bindbc-sdl:
  testing ~master depends on bindbc-sdl ~>0.16.0