Any on-disk format changes recently?

[Asdo]

Dear XFS people
I am tracking a nasty bug for which I would need to regress the kernel 
version from 2.6.31 down to 2.6.28 or maybe even 2.6.24.
I have to do this on an important fileserver full of important data on 
XFS filesystems which were created on 2.6.31.
I also need to *write* to the XFS filesystems after regressing the kernel.
Do you see any problems with this? Have there been on-disk format 
changes for XFS since 2.6.24 that could trigger data loss? (or with much 
minor concern, fail the mount?)

Thank you
Asdo