I’ve been on an extended strike once so I speak from that experience but also “traditionally” those on probation would not picket but most certainly not show up to fly struck work either. There are plenty of other duties to do during a strike that don’t involve picketing in your uniform such as helping to run the strike center.
The thing to keep in mind is that when your union finally reaches a deal with your company, it will most surely have a clause that any hostages that were taken by the company need to have their jobs reinstated. That’s almost a given during every strike.