Is there any PDFBox sample to make Document Timestamp Signature as LTV enabled?

Question

I am trying to implement Document Timestamp (a separate signature with type DocTimeStamp and SubFilter ETSI.RFC3161) and Signature Timestamps (timestamp token as unsigned attribute to current signature). I am trying to understand what all changes in signature dictionary are required. Below are my findings:

1. For Document Timestamp, I need to add the certs, CRLs and OCSPs to DSS dictionary. A separate DTS dictionary will also be created for contents like ByteRange , contents , SubFilter etc.
2. If it is a subsequent signature, I need to add the Certs, CRL and OCSPs for previous signature to existing DSS dictionary.
3. For Signature Timestamps, I just need to add certs, CRLs and OCSPs to DSS dictionary along with existing revocation info.

Please confirm , if my understanding is correct or I am missing anything. Also, please suggest code samples for fetching the certs, CRLs and OCSPs for timestamp signatures and embedding it to DSS dictionary to make it LTV enable.

I have read the specs and tried PDFBox samples but those timestamp signatures are not updating the DSS dictionary.