We're currently running 13.3R6.5 on cr2 and 13.3R6-S7, a service release, on cr1. We needed the service release because of T112639, but it's not very well tested due to its nature and it's not entirely stable (e.g. GRES/NSR doesn't work, kdump core dumps).

Juniper said that 13.3R8 should be out in mid-October or so, which would also fix T112639. We should investigate upgrading both routers to it e.g. at the beginning of November. This should probably happen after cr1's QSFP+ replacement (tracked by T92616).