No, it's impossible to go via mainline. Because DDU is mentioned as cancelled. No train can enter PNBE-JAJ-ASN mainline by bypassing DDU. Most probably, it'll go via BUI-CPR-PPTA-PNBE or BSB-BUI-CPR-HJP-BJU-KIUL.
And it will not run between UMB-DLI. Infact, it'll be diverted between UMB-ASN through SRE-MB-BE route.