I have been trying to specify supported versions of the SDK packages following the documentation but several cases did not work:
Did not work:
>=3.9.0-0 <3.10.0
>=3.9.0 <4.0.0
~3.9.0
^3.9.0
A user of my packages discovered it:
Steps to reproduce:
  1. Create a world project
  2. add ONLY the VRChat SDK - Base 3.8.2 AND VRChat Package Resolver Tool 0.1.29
  3. add https://cyanlaser.github.io/CyanPlayerObjectPool/ listing to VCC
  4. add https://guribo.github.io/TLP/ listing to VCC
  5. scroll down to TLP UdonVoiceUtils and try to add 3.0.2 to the project
Result:
Error occurs in package.json of TLP UdonUtils which already supports VRC SDKS 3.9.0
Expected behaviour:
  1. VCC installs VRC World SDK 3.8.2
  2. VCC installs TLP UdonUtils 11.5.3 (last version that supports VRC SDK 3.8.x (3.9.0 explicitly excluded!)
  3. VCC installs TLP UdonVoiceUtils 3.0.2