You don't pay a miner fee when you withdraw from strike to Phoenix. Custodial lightning services handle channel management for you. If you pay attention to that video, it cost me 9 sats to make that transaction. You'll pay a single miner fee when you splice out to cold storage.
Discussion
Buy 100000 sats on strike. send to Phoenix. Pay a fee for initial channel open through the LSP. Assume its batched for a lower fee.
Dont spend any
Tomorrow, DCA again, send to Phoenix. Phoenix may have opened with more liqudity on their side, so no fee.
Repeat every day for a month. At some point, all that liquidity moves to your side, and either another channel needs opened, or a splice. Either way, theres another fee.
Check your fee schedule and channel liqudity. Manage appropriately based on circumstances.