It is not the onshore market itself that The BALPA membership as a whole won't support, its the single pilot ops.
As the final paragraph in the BALPA argument against the age 60+ campaign, sent to the PAS CC, the BALPA Flight Safety Committee quoted BALPA policy:
Their quotation below.... with my 'sic' added!
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MINIMUM CREW OF TWO PILOTS
That the policy of the Association be to obtain by all possible means the necessary change in legislation to enforce the requirement that a minimum of two pilots holding current Commercial Licences and Instrument Ratings and qualified on the type should be carried on all fights (sic) under IFR and at night on public transport aircraft, including those certificated for single pilot operation.
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