Hey Laura,
I would advise staying on 8030 code stream for now as it is the most mature. I would say move to the latest patch, however. Generally speaking you can make a direct jump from 8030 to 8070. If there are caveats, they should be listed in the release notes. If you are ever uncertain, you can open a case and TAC will let you know as well.
Ben Beck, RCNA, RCNI, Principal Technical Support Engineer
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