Found this article from earlier this year. It does a really good job of explaining all kinds of roster/salary related topics. Most every question can be answered here, just short of reading the actual CBA. I learned some new things.
Nice

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This quoted portion, from the article, clarifies a few things for me.
"PRACTICE SQUADS
Roster size: The practice squad now consists of 16 players as of 2023. The max was 12 players in 2021.
Eligibility: The rules for roster size and eligibility for the practice squad
were amended by the NFL and NFL Players Association in May 2022. Players with no accrued seasons and those with fewer than nine regular-season games in their lone accrued season are eligible for the practice squad. Teams can also have a maximum of 10 players who have earned no more than two accrued seasons. Each team can have up to six players with unlimited accrued seasons on the practice squad. However, the number of players in the last two categories cannot exceed 10 players combined.
Standard elevation addendum: Now included in all practice squad contracts, the standard elevation addendum allows teams to move a player from the practice squad to the active/inactive list for one week and then back to the practice squad without subjecting him to waivers. Under this addendum, a player reverts back to his team's practice squad on the first business day after the game in which he is elevated. These players receive the applicable minimum salary for a player with his number of credited seasons (prorated for one week of regular-season pay or the applicable postseason amount). This clause can be used by a team for a maximum of three regular-season or postseason games per player per season. Each practice-squad player can be elevated for a maximum of three regular-season games in the same league year. After this, any subsequent elevation of the player will require the team to add him to their 53-man Active/Inactive List. The team must then waive or terminate his player contract before the player can be re-signed to the practice squad. If the player is re-signed to the practice squad this way, the player is again eligible to be elevated for the previously mentioned maximum of three games."
Good summary. I have no interest in wading thru 456 pages of lawyer talk. Thanks for posting.