I did not know the difference between adaptive and static security:
Adaptive security is a stronger notion of theoretical security over static security. Static security models a security experiment with the adversary picking corrupted parties all at once, at the beginning of the experiment, before it is allowed to interact with honest participants in the protocol. Adaptive security allows the adversary to adaptively corrupt participants throughout its interaction in the protocol. Hence, adaptive security models real-world attacks more closely.
Now having learned it, I'm still a long way from fully understanding what's going on here.
the main contribution of this paper is to give a tight(er) proof of full adaptive security for FROST in the Random Oracle Model (ROM) and Algebraic Group Model (AGM), under the Algebraic One-More Discrete Logarithm (AOMDL) problem. We additionally show adaptive security for t/2 participants in the ROM+AOMDL only.
Whatever the case, I like FROST and I'm excited by any developments around it (because I'm hoping they mean we'll get more FROST stuff for retail soon). Perhaps @bitcoinplebdev has a better handle on what's going on here.