Using up to 4 DX clusters or remote beacon network nodes, the DX Submit web cluster, and one or more local WSJT-X instances as input, the freeware
DXLab Suite maintains an active DX database with one entry for each active station near a particular frequency in a particular mode. This makes it possible to
1. identify the operating patterns (bands, modes, times) of stations I'd like to work
2. identify propagation openings between my QTH and stations I'd like to work
When I was chasing ZC4GR on FT8 last year, I first filtered the active DX database to show ZC4GR's FT8 activity by band and time of day:

Then I filtered the database to show all stations in ZC4, 5B4, TA, OD, 4X, and SU spotted by stations within 500 miles of my QTH near Boston MA, revealing the propagation openings between ZC4 and me:

Noting the primary overlap between ZC4GR's operating activity and the propagation openings, I monitored the 20m FT8 sub-band from 12Z to 23Z.
Success!