1. I am not a regional pilot.
2. I totally sympathize with the plight of the regional pilots in the US
3. I don't recommend this action to anyone.
Each company is different and a refusal to fly is a contractual violation that is treated differently by contract, if there is a CBA, at each airline. I do know that in many contracts an unexcused absence that can be tied to a "job action" can result in termination that is unlikely to be overturned by an arbitration hearing at a later date.
That is generally how it works in the US under the Railway Labor Act. Almost all contracts allow a pilot to appeal his termination to a "neutral arbitrator" who is not association with the company. The scope of previous arbitration awards are not supportive of illegal job actions. Those types of actions are specifically described in the Railway Labor Act as violations of the "status quo" of the contract, and therefore illegal.