Terraform plan/apply not incrementing version number in GCS backend

I am doing upgrades from TF14 → TF15 and I made sure all my plans return cleanly and I have started to run “applies” everywhere.

On certain modules, it updates the version in my GCS bucket backend as:

  "version": 4,
  "terraform_version": "0.15.4",
  "serial": 3,
  .....

Which is correct. However, there are some modules which keep the same “0.14.11” in the “terraform_version” and never gets updated. I have tried init and refresh without luck.

This seems to be hit and miss. I also did a terraform state pull and interestingly enough that returns the correct version of “0.15.4”.

terraform --version
Terraform v0.15.4

Expected Behavior

I would expect the correct version in the default.tfstate in my GCS bucket backend.

Actual Behavior

Some statefiles have the old Terraform version number.

Additional Context

I am using Terragrunt 0.29.6