as mentioned in previous answers, there are serious problems with YAML Gedmo definitions. There are two (maybe three) kind of formats which Gedmo YML is using. And when we fixed the first one, we broke the second one.
The first one is using referred "- anything" format and the second one "anything" format.
And unfortunately, it isn't possible to maintain such inconsistent form. So yes, you're right that versions before 3.2.10 exported correctly mentioned situation (soft* vs -soft*) but incorrectly exported another half of use cases. And when we fixed the second half, we broke the first one.
Because of such inconsistency together with official statements that Yml will not be supported in future Doctrine versions (for example here) we decided to surrender our attempts and left yml format in current state.
The best way what can our users do is to re-export all definitions to the different format. Because you (and a lot of other users) are using Skipper to export Doctrine2 definitions, there is no reason to export it to inconsistent YML instead of fully supported and explicit XML.
It's a matter of few clicks to change the format from YML to XML. After that, you will get fully functional export and complete Gedmo support.
Although we loved to support all formats (including the forbidden ones) we're not able to support such inconsistent format which using several forms to describe the same thing.
Thanks for understanding.