My suggestion of free services was envisioned to use novice agency staff, namely people who have never driven a bus but do have a license and can be quickly trained and passed in PSV (presumably by managers). Given a head start of 6 weeks, it's possible I think, at least for a reliable skeleton service that could be used for PR value. There's no shortage of people out there ready and willing to work for as little as £11on on a short term basis, if the promise of doing a good job was a permanent driving job at something like £12.50. Agency staff are used to working overtime and shifts at basic rate. Agencies do charge a finder's fee for short term work like this, but for a big corporate client like Stagecoach, for a special one off contract, the agency's terms could be modified to make it as cheap as possible.
I was intrigued to see an agency (Pertemps) refusing to supply staff to a striking school, so that might be an unexpected problem!
As it stands, it seems like the ordinary tactics might suffice. The strike as barely mentioned in my social circle, and more of an on so that's happening then, not with any strong support for the drivers, even though these people are occasional users of the Sunderland routes. Drivers perhaps needs to realise that the basis of this crisis is something that effects everyone. Screwing over pensioners panicking about their heating or agency workers trying to get to their poorly paid jobs at unsociable hours is not a winning strategy, especially if the support for the strike is already so weak that a good proportion of daily normal hours commuters will only be mildly inconvenienced.
RE: Sunderland Stagecoach Strike