[PC Gamer]

Interesting observation...

First player to join: Server console shows stage 1,2,3,5,6 (missing stage 4)
Second and subsequent players join: Server console shows stage 1,2,3 (missing stages 4,5,6)

Compiler version: 1.10.0.6478
sm version on console: Build ID: 6478:a8b9da9a

Since it worked for you I will install a newer version of Sourcemod and test it. Thanks for your feedback. It helps with the troubleshooting.