The Eastern Main Line will connect the voivodship capitals of eastern Poland

Logistyka 
09/09/2021 (Poland)

The Eastern Magistrala, i.e. Rail Carpatia, will connect Olsztyn, Białystok, Lublin and Rzeszów.

The Ministry of Infrastructure asked the European Commission to extend the TEN-T network so that Rail Carpatia (RC) would connect Olsztyn, Białystok, Lublin and Rzeszów. 

The ministry assumes that Rail Carpatia would run southwards from the Białystok station via a single-track and non-electrified railway line no. 32 via Bielsk Podlaski to Czeremcha. Next, the route would lead south along the railway line No. 31, while on this section of the Czech Republic (like the Polish proposal to supplement the TEN-T comprehensive network) it would have two variants.

The proposal of the Department of Rail Transport of the Ministry of Infrastructure concerns the modernization and electrification of the railway line No. 31 to Siedlce with the simultaneous addition to the TEN-T network and the priority electrification of line No. 31 along the entire route, so as to fully use the Siemianówka-Swisłocz railway border crossing (ultimately it would be a variant dedicated to handling freight traffic from Belarus),

The CPK proposal assumes that a new railway line no. 631 Fronołów - Biała Podlaska - Milanów would be built from Fronołów on line 31, after the construction it will be used for passenger trains. 

The implementation of this project will enable, among others achieving shorter travel times on the Lublin - Białystok section (by approx. 90 minutes to the current travel time) and the inclusion of Biała Podlaska in rail connections on the north-south route.

Source
https://logistyka.rp.pl/szynowy/art18900451-magistrala-wschodnia-polaczy-stolice-wojewodztw-wschodniej-polski