Updated BGP-LU route in app-rib is not propagated to neighbor

Scenario is as follows:

1. bgp connection to router is up
2. bgp labelled unicast (bgp-lu) route is injected through app-rib
3. it is correctly advertised to router
4. bgp-lu route in app-rib gets updated with change in label-stack
5. change in route is reflected in app-rib adj-rib-in/effective-rib-in, but not in loc-rib and peer adj-rib-out
6. updated route is not advertised to router