iBGP session stuck in Active after moving to loopback peering

AS 64500 has two edge routers, R1 and R2, joined by one link (10.0.12.0/30) and running OSPF. Last night the team moved their iBGP session from the link addresses to the loopbacks (R1 10.255.0.1, R2 10.255.0.2) so it would survive a future second link. Both routers were changed from the same template. Since then show ip bgp summary on both routers shows the neighbor in Active, and R2 has lost every route R1 learns from ISP1.