This is Colin with Bullhorn Support.
There shouldn't be an issue using REST to update a note on a Lead to also associate it another entity. You would simply run the call to update the note's jobOrder(s) fields as needed to reference a job.
This can also be done in-app by opening the note and updating it there.
I do want to mention that once a Lead is converted it is best practice to stop using the Lead record for most uses and start using the newly created Contact. The notes from the Lead are carried over on Contact creation but any further updates to the Lead are not pushed through to the Contact. So I recommend updating new Contact's notes to point to the vacancies you desire them to.
Enterprise Support Analyst
B U L L H O R N
Staffing and Recruiting Software, On Target, On Demand
617-478-9126 (US Support)
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