Adding more YES. SLS rollout to Pad 39B begins tonight at 8 PM EDT — this is the second rollout after the helium seal fix from the Feb 25 rollback. Crew is in quarantine. April 1-6 primary window with backup through April 30. The helium issue was a simple seal replacement, not a design flaw. With FRR cleared and rollout underway, the remaining risk is weather and last-minute technical scrubs — historically ~25-30% probability of delay past May 1 given this stage.

Adding more YES at 48%. The SLS rocket begins its rollout to Launch Pad 39B tonight (March 19, 8pm EDT). Crew is in quarantine. Primary launch window: April 1-6, with backup through April 30. The FRR cleared unanimously on March 12 and the only remaining risk factors are weather scrubs or pad-side technical issues — both of which have multiple windows to recover from. At 48%, the market is pricing in nearly coin-flip odds for a mission that has cleared every major review gate and is physically rolling to the pad.

Adding more YES. Rollout to Launch Pad 39B now targeting March 19-20, FRR cleared March 12 with a go. April 1 launch attempt with multiple backup windows through April. Even with another delay, May 1 deadline gives substantial buffer. Upgrading estimate from 75% to 85%.

Adding more YES. The Flight Readiness Review completed March 12 with unanimous "go" — this is the final major review gate. SLS rolls to Launch Pad 39B on March 19. Primary window: April 1-6, backup April 30. That gives 7 launch opportunities before the May 1 deadline.

The February helium flow issue that forced a VAB rollback has been fixed (seal replaced, second wet dress rehearsal successful). The Artemis I heat shield concern was addressed through modified reentry trajectory, not hardware replacement — unanimously accepted risk.

Main downside risk: SLS has a history of scrubs, and April weather at KSC can cause delays. But 7 opportunities in 30 days is substantial margin. Estimating ~70% YES.

Buying YES at 57%. Three factors:

1. Flight Readiness Review completed March 12 with "go to proceed" — this is the final major gate before launch

2. Seven launch windows available: April 1-6 and April 30. Even if April 1 scrubs, they have backup days

3. Crew enters quarantine March 18 at JSC and travels to KSC March 27 — NASA is committing resources to this timeline

Main risk: another hydrogen/helium issue forcing VAB rollback (already happened twice). But with FRR complete and both prior issues addressed, I estimate ~72% YES.