Submission validates locally but fails with Evaluation error

Hello,
When running my estimator locally with whest smoke-test, whest validate and whest run, everything works, but when i try to submit it either via web or CLI, i get this cryptic error message:

participant subprocess crashed: unexpected frame type 'result'; expected 'predict_start'

Locally, i use whestbench 0.12.0rc0, but on the submission page, tab configuration, i can see that the server seems to be using version 0.11.0rc0

Can you advise me on what could be the problem here ?
Thanks