Bit of light background reading here
about BA and that wetlease.
From Para 36 ...
”
36. BALPA also raise two other points: circumvention of the Employment Agencies Regulations 2003 and Article 11 of the Convention on Human Rights (the right of assembly). The CAA does not think that these points are of relevance to the application for approval of the proposed operation submitted by BA. In the case of the 2003 Regulations, the prohibition in those Regulations is on an employment agency, not on an employer or another employer, such as Qatar Airlines. The point in relation to Article 11 is not relevant since the approval, if granted, would not limit or restrict the right of industrial action by the mixed fleet cabin crew.”
So in that case it appears the CAA were OK with approving a wetlease because doing side steps any regs regarding agencies and strike breaking, and using a wetlease doesn’t prevent the workforce from indulging in IA...so that’s alright then...