I agree - I suppose obviously direct entry SCCM will have to have experience with another airline. I know EZY does direct entry SCCM and they require (1 or 2 years can't remember!) which is the CAA minimum. Experience is crucial so I think 2-3 years is reasonable as a minimum. However seniority is different as it is more restrictive and often it might mean people who have only been here for 10 years plus can apply.
I wouldn't really expect the seniority/working positions changing for current crew- I was just highlighting why although some people think seniority is the best way - I think it should be used for some things but promotion/working positions not really. As for the US airline's systems of seniority based rosters -
That is very demotivating for newer crew, especially as the biggest US carriers from what I hear have low attrition meaning the newer crew will take like 30 years to get the best routes!!
Having said all that, I do not agree with having a ''waterstone's model'' aswell - but I think that is Unite's spin.