It is not necessarily an issue to remain on 6.51. It’s just a potential reason why I wouldn’t be able to replicate as the panels I have are all updated to 6.81.
It also doesn’t necessarily mean it’s a bug is on all 6.51 panels, but it definitely helps in narrowing it down.
You could try updating and seeing if the same issues occur. However, other impacts from the SDK update would apply. Some users reported issues with non-S2 locks like old Kwikset models. Issues with some Schlage locks were reported. A long thread is found here.