Hi Diane,
if you go for 9.12 or 10.0 depends on how long you want support for it.
9.12 is a regular release with 3 years of Standard Support which can be extended afterwards.
10.0 is an Innovation Release which has only 1 year support which cannot be extended.
Additionally you have to explicitly opt in for the innovation releases where as the regular releases are made available in the normal way via installer.
Regards,
Holger
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