Question about pose prior in current three SfM pipelines

Hi, development team, I would like to ask some questions about the role of pose priors in current SfM pipelines. According to https://colmap.github.io/faq.html#choosing-between-incremental-global-and-hierarchical-sfm , COLMAP offers three SfM pipelines: Incremental mapper、Global mapper and Hierarchical mapper. I have written the pose prior info into the database.db file, used pose_prior_mapper(which belong to Incremental mapper, https://github.com/colmap/colmap/issues/2976#issuecomment-2513848213) and could get correct scale sparse model.

Here is my question:

1. Does Global mapper support reconstruction with pose priors? In PR https://github.com/colmap/colmap/pull/3904#issue-3768372270 says "global mapper read pose priors inside the mapper logic." But in PR https://github.com/colmap/colmap/pull/4384 it seems that colmap doesn't use pose prior in BA currently. So, what's the role of pose prior in Global mapper?Is there any help to sparse reconstruction if i write pose prior info into databse.db?
2. If pose prior not used in Global mapper , how can i get correct scale sparse model? Use model_aligner?
3. Same as 1, does Hierarchical mapper support pose priors reconstruction?

Looking forward to your reply!