My question relates to the heydays of GM power on the Irish network, so I suppose up to the late 90s. Would it be conceivable that from time to time depots or yards would end up with surplus motive power, or the wrong mix of power? Example, at the end of the beet season, knock specials etc.
What I'm really asking is, if this happened, how was stock re-allocated? Light engined to new destination? Light engine but part of a freight or passenger consist?
The reason I'm asking is that I clearly recall in the mid 90's seeing 3 x 141s (and other oddball mixes) on both ammonia trains and evening passenger train that were Arklow/Rosslare bound. I'm wondering was this when IR was at that low point just before the arrival of the 201s, when everything was on its last legs? In this case the extra loco being a thunderbird. Or were extra locos 'in transit'?