KNL-725, the field was converted to TIMESTAMP WITH TIME ZONE, however this was reported by two people to cause problems with clusters going out of Sync.
This entire issue came up because both Omer (at rice)
And Jaco (At opencollab)
said that there were warnings about sessions getting closed and clusters leaving when the field on SAKAI_CLUSTER was converted by the 2.9.x script to "TIMESTAMP WITH TIME ZONE". It should fix the DST problem but caused this other problem.
Leaving it as DATETIME (the existing field type) would still leave the DST problem, converting to TIMESTAMP would give you increased precision but still leave the DST problem.
I believe that converting to TIMESTAMP WITH LOCAL TIME ZONE could potentially resolve both clustering and DST, or it might break still break the clustering. I'm going to commit this fix.
There was also a commit to
KNL-734 which changed SAKAI_EVENT and SAKAI_SESSION which should also match this type.