IFALPA has disseminated a Safety Info. Bulletin issued by EASA (European Union Aviation Safety Agency). "Global Navigation Satellite System Outage Leading to Navigation/Surveillance Degradation", Safety Information Bulletin, Operations - ATM/ANS, SIB No. 2022-02 (March 17, 2022).
Reference is made to Ukraine conflict and other areas as well.
The page on IFALPA's site from which the bulletin can be downloaded is:
https://www.ifalpa.org/publications/...radation--3583