BGP stops advertising after upgrade

Hello , 

we have an LTM VE in  a HA cluster . We have defined a couple of route domain (RD) and have enabled BGP/BFD for these route domains .

There is a BGP routing configuration present (imish -r RD) . In this configuration peer devices are defined , and by putting RHI (route health injection) we advertise our virtual servers towards these bgp peers .

The current setup is running on version 13.1.1.5 and is working since long time without any issue.

AS v13 is going end of life we tried to upgrade recently to v14.1.5.2 . The upgrade itself went smooth . New version was activated , all pools and virtual servers were present as before. Initially all looked ok .

When we checked out BGP peer (show ip bgp summary) we could see that the peering was established , again this looked ok . But when checking the advertised routes , no routes were being advertised . 

"sh ip bgp neighbour x.x.x.x advertised-routes" --> showed no routes present , whereas before we had about 10 virtual servers being announced in v13

I'm aware of article https://cdn.f5.com/product/bugtracker/ID1031425.html concerning BGP advertising . But this is the case when you receive a route , and try to advertise it then from F5 (back to front advertising) .

In our case F5 is end device , and just announcing these virtual servers. So we are not receiving any BGP update and then sending these routes on .

IN the end we needed to rollback to v13 again , by booting from partition with old version . Once this was done all started working again including BGP .

Any idea what could be issue here ? (i've pasted our BGP config here below , it's quite basic)

we use a routemap for blocking incoming updates (DENY-ALL) and with routemap  "KERNEL2BGP" we control which virtual servers we can advertise . (each ip we want to announce it mentioned in this routemap)

router bgp F5-AS
bgp router-id F5-selfIP
bgp always-compare-med
bgp log-neighbor-changes
bgp graceful-restart restart-time 120
redistribute kernel route-map KERNEL2BGP
neighbor peer-IP remote-as "remote-as-nr"
neighbor peer-IP description "xxx"
neighbor peer-IP update-source selfip-address
neighbor peer-IP password "xxx"
neighbor peer-IP timers 3 9
neighbor peer-IP fall-over bfd
neighbor peer-IP next-hop-self
neighbor peer-IP soft-reconfiguration inbound
neighbor peer-IP route-map DENY-ALL in