We have mobile NWs in both Asia and Europe and also experience a lot of issues with PTP, - almost with every vendor.
The instabilities, SW-bugs etc. related to PTP seems to indicate that very little testing of this code has been done in production networks. In some deployments we have been able to produce a clock service by installing GNSS on the cell-site. However, in other countries there are regulatory directives that the phase sync must be PTP/Network based.
 
Currently, the optical domain is causing us huge problems when we try to engineer a T-BC/PTP solution. This is due to the path asymmetry that exist in the WDM/fiber domain. In some networks we have a lot of DCF in the fiber path and the only way we can get visibility in the asymmetry on these fiber hops is to measure in both direction:(
Also, running T-BC over WDM/OTN will simply not work as the phase error introduced more or less eats up the phase error budget for 4G/5G TDD-service. 

best regards,
Geir

On 5 Sep 2020, at 00:17, Macho Pellegrini via NANOG <nanog@nanog.org> wrote:

Hello everybody,

We have deployed PTP in our mobile NW since late 2019 as a part of the 4G/5G, however we are seeing a lots of instabilities and interop issues, a lot of the issues have ended up with SW bugs in the OS, I have no specific question, however I got the impression that the technology/protocol is not yet mature, anybody here got his hands dirty with PTP?

Thanks,
MP