You might be right about that it references other packages. In your current 2008 packages, I assume that there the location of the package is the full file path? In SSISDB you won't have those same FilePaths, as within SSISDB they don't exist.
As it happens the file paths are the same between the Dev box and the UAT box but I take your point and it's something to bear in mind.
Is opening your Integrated Services project from SSDT not an option, and then deploying it from there not an option? I realise that if this is a large project it's going to take time, but you could amend the tasks to reference the other packages within the project, rather than FilePath, at that point and then deployment "should" be relatively simple.
Not at the moment; the best I could do is use BIDS on the the UAT jumpbox with an untouched 2008 version of the package. That would essentially mean having to start from scratch though and I reeeaally don't want to do that. When it comes to going live its a possibility. I might be able to do that on the live servers before we cut things over. This is not ideal.
I'm trying to write the release plan for go-live and I wouldn't be happy writing anything definitive until I've successfully migrated the packages between the two versions.
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