Unfortunately I forgot to checkpoint my project. Now I have about 30 change packages with several released software versions within. How get I get the source code of those releases?
Is there a possibility to download the content of a change package? Or even better to download a sandbox after e.g. the first 4 change packages?
Have you considered the following approach:
This way you will be able to reconstruct the missing checkpoints - even if only on this variant.
You could also try Merge Development Path, which executes based on Change Package. As conveyed by @ML_7184897 , create variant from previously created Checkpoint and then try with Merge Development Path. The advantage of this feature is, the changes will be first applied on sandbox and on validation, it will be applied to project. So its perfectly safe.
For different Check Packages, the execution needs to be executed separately.