Welcome! This forum has a treasure trove of great info – Scouters helping Scouters! Just a heads up, though - all content, information, and opinions shared on this forum are those of the author, not the BSA.
Long story with way too much drama, but my family has been kicked out of our troop. 2 of my sons will be old enough to join a Venturing Crew in a few weeks and that is the plan for their future advancement toward eagle.
If the troop deletes them from Scoutbook before they formally join the crew , will all their advancement data be lost?
First off, troops are not able to delete Scouts or adults. All they can do is end the membership in the unit. All advancement is retained in Scoutbook.
When you submit the new youth application for your sons, make sure you write their BSA Member ID on the application. This will help the registrar find their existing records and not assign a new number.