A more "up to date" (circa 2021) Schedule 17 planning application for the WCML bridge can be found on Lichfield District Councils planning portal (application reference 21/01249/HST) ...
planning.lichfielddc.gov.uk
As noted by others, the WCML is not being realigned - the bridge is being constructed off-line and will be jacked into place when ready. Presumably that's cheaper (less land and material etc required than diverting the WCML,) requires a shorter closure of the WCML and means no alignment changes on the WCML (one wonders whether such could impact WMCL signalling, timetable, speeds profile, etc.. if they'd gone that way? Over to the experts...)
(I use the term "jacked" in the loosest sense - whether it will be "shoved" by jacks a la Werrington or lifted on some modular transporters a la the Cow Lane Bridge in the Reading remodelling, I do not know.)