A boatload of TV talent just flooded onto the market.

The rash of cancellations on Thursday afternoon from across the broadcast nets makes free agents of highly sought after TV stars like Nathan Fillion (“Castle”) and Connie Britton (“Nashville”), along with John Stamos (“Grandfathered”) and Rob Lowe (“The Grinder”).

ABC on Thursday afternoon conducted its annual pre-upfront housecleaning, making renewal, cancellation and pickup decisions that speak volumes about the network’s priorities. Some of the cancellations were so expected as to be anti-climactic (read: “Galavant”), and some were surprising given the behind-the-camera drama that played out in public (read: “Castle”).

ABC, like CBS, has undergone regime-change in the entertainment suite. The new bosses, ABC’s Channing Dungey and CBS’ Glenn Geller, are looking to put their stamp on the schedule, clearing out the old and infirm to make way for what they hope will be happy, healthy newborns that reflect well on them.

ABC’s habit during the past few years of giving short orders to numerous shows means it has more to whack as the day of reckoning (its May 17 upfront presentation) approaches.

The curtain fell on “The Muppets” after the effort to put a hip spin on the beloved Henson Co. franchise fell flat, not once but twice this season. While the mission ended for “Marvel’s Agent Carter,” its plucky heroine, Hayley Atwell, was dispatched to the present day to lead a legal procedural, “Conviction.”

ABC offered some surprises in the shows that did get renewed, notably the comedy “The Real O’Neals.” That may say a lot about the state of its comedy development.

The third season nod to anthology drama “American Crime” was not a shock but it was not a lock, either. The same goes for midseason drama “The Catch,” which surely was helped by its Shondaland parentage. But “Dr. Ken,” on the other hand, has been straight down the middle from day one, aided in no small part by its low-stress Friday time slot.

CBS said a final-final goodbye to the “CSI” franchise in pulling the plug on “CSI: Cyber” after two seasons. That ends the streak of the acronym that become synonymous with the CBS drama milieu since the mothership premiered in the fall of 2000. There’s no one in the industry who doesn’t think that “CSI” will rise again in some form (there are already rumblings about a possible new entry for the CBS All Access SVOD service), but the cancellation nonetheless marks a moment in time. And James Van Der Beek is back on the market.

CBS finally acknowledged the obvious in sending “Supergirl” to the CW for its second season. Yet the renewal for ensemble comedy “Life in Pieces,” from 20th Century Fox TV, defies the current push at CBS and other networks to own everything that they air.

Fox admitted defeat with its freshman comedy crop, cancelling “The Grinder,” “Grandfathered” and “Cooper Barrett’s Guide to Life,” along with the animated “Bordertown.” There had been some expectation that Rob Lowe’s “Grinder” would get a new lease on life given that it had some “New Girl”-esque cool factor. Now Lowe and “Grandfathered’s” John Stamos are once again open for business.