Question about restriction of S/T and monster zones

[summer bear]

https://duelingnexus.com/replay/a278ceaa-cf3d-4059-8a1b-7608030c62cc

Hi, in this game I activated Shangri-Ira, my opponent responded by activating hornet drones and summoning a token in a monster zone which was going to be unusable due to Shangri-Ira.

He was able to successfully summon the token, but the monster zone underneath was still hit by Shangri’s effect, you can see the X under the token.
The X was clearly visible once the token left the field.
Is this correct?
Because I thought that since he summoned the token, I couldn’t take over that monster zone.
Or maybe I don’t know completely how restriction on S/T and monster zones works.

Thanks for the help!

[white hawk]

If you target a zome for Shagra-Ira's effect, a monster can still be summoned into that zone before Shang's effect resolves. Once that monster leaves that zone, the zone will be unusable

[summer bear]

Ok

And I cannot select as a target for Shangri’s effect a zone which was already occupied before the effect’s activation, right?

[white hawk]

Correct, zone-locking effects must target an unoccupied zone at the time of activation

[summer bear]

Ok