At the heart of the problem are the so-called advance paidresiduals.
That is a portion of a performers per-episode fee check, which counts towards future residual payments.
That will change when the SAG-AFTRA tentative agreement with the AMPTP is ratified.

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Reps were walking the picket lines, taking reduced or no salary during the strike, an agent said.
We have reached out to SAG-AFTRA for comment.
Studios practice to bundle advance residual pay into episodic fees is a fraught one.

A salary by definition should reflect an actors value as a performer and reward their work on a show.
Thats not something studios would likely go for.
Instead, with the new rules, SAG-AFTRA sought to bring clarity for performers on the issue.
Actors start receiving residual checks after the advance payment is fulfilled.)
The upfront residuals will be processed the same way SAG-AFTRA handles the traditional post-run ones, guild sources said.
They will be added to the 4 million residual checks the union processes and sends to its members yearly.
The new level of animosity between SAG-AFTRA and the agencies adds to an already distant relationship between them.
Those boutique agencies play a crucial role in Hollywoods ecosystem.