It depends on how PSS and SSS symbols are located in a frame, UE will understand whether network is using FDD or TDD during PSS and SSS .
Each band is categorized either as FDD or TDD band. UE may have support of multiple bands and those supported bands may be the combination of FDD and TDD. Please correct me if I am wrong.
If an operator in ine GEO supports TDD and other GEO supports FDD , then will UE support this feature or UE is designed either TDD or FDD ?