Most BBC staff in Bangor joined the strike action on Friday, with just five out of more than 100 said to have crossed the picket line
Media and entertainment union Bectu is considering taking legal action against BBC Wales, after four editors posts were made compulsorily redundant.
Members of the union in Wales carried out a 24-hour strike on Friday (30 September), which they hailed a success claiming services were "seriously disrupted".
The union said it took action after talks with the broadcaster "failed to deliver concessions sufficient to resolve the disagreement".
According to the strike organisers, BBC Radio Wales show Good Morning Wales was replaced by a repeat of arts programming while other programmes were cancelled.
The union also claims that in Bangor only five people out of a workforce of around 110 turned up for work on Friday morning, although the BBC disputes this and says the figure was actually 20.
Bectu's Welsh organiser David Donovan told Journalism.co.uk that Monday (3 October) had been the last working day for the affected members of staff.
He added that the union has not heard from the BBC since the action was carried out and is therefore now preparing documents for their solicitors, and considering legal action over the dismissals.
BBC Wales had not responded to a request for comment at the time of writing, but a spokesman previously said the broadcaster is "utterly committed to working with all individuals at risk of redundancy to seek out alternative employment".
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