The Cyphal specification documents are maintained here.
Compared to v1.0-alpha, the differences are as follows (the motivation is provided on the forum):
The physical layer specification has been removed. It is now up to the domain-specific UAVCAN-based standards to define the physical layer.
The subject-ID range reduced from [0, 32767] down to [0, 8191]. This change may be reverted in a future edition of the standard, if found practical.
Added support for delimited serialization; introduced related concepts of extent and sealing. This change enables one to easily evolve networked services in a backward-compatible way.
Enabled the automatic runtime adjustment of the transfer-ID timeout on a per-subject basis as a function of the transfer reception rate.
This version is expected to be followed by v1.0 stable in less than 6 months.