Polygon PoS finality and validator rotation limits for migration

Goal is to move a small application to Polygon PoS with minimal user-visible downtime using a parallel deployment and bridge-based data sync.

The design relies on documented PoS behavior: a rotating validator set with stake-weighted selection, a reported ~12 second block time, and finality after a set number of blocks. Validator rotation is reported to occur every ~5,000 blocks, which affects which nodes are active during a cutover window.

The cost-security balance for a small deployment remains unresolved. A smaller operational validator footprint reduces cost but changes exposure to stake concentration and uptime risk, while a larger footprint increases cost and operational overhead.

Questions:

• What is the current documented finality depth and block time for Polygon PoS?
• How does the reported validator rotation interval interact with a DNS cutover after bridge sync?
• What documented limits apply to validator set size versus security guarantees for a low-throughput application?