Quick question about Caribbean B2Bs. Has anyone attempted them, and can you get a boarding pass for your return at the departure point?

Example being BA2157 from Antigua to Basseterre. Booked arrival SKB 1520, BA2156 from SKB to ANU departs at 1650.

90 minutes on paper, but the question is how you're dealt with at SKB. BA long haul International check-in close is 60 minutes before departure, so technically doable, but the BA booking system won't give a valid same day return booking.
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