MX64 Customizing Block Page when using Custom Splash URL

[cfemfrl]

Hello, all,

I have one VLAN that has click-through splash page for which I've created custom themes and modified the http and css to have customized splash and block pages.  By "block page" I'm referring to devices blocked by individual device policy, not content blocking.  This setup has been working fine for quite some time.

Now I'm setting up another VLAN with the same basic setup, but the splash page is a "Custom-Hosted Splash Page".  Initial testing seems successful with access control, walled garden, etc. and have proper click-thru splash and block behaviors.  

So, my question is:  How do I customize the/a block page for this new VLAN?

[SoCalRacer]

According to this doc the block page can't be customized, but the message can.

https://documentation.meraki.com/zGeneral_Administration/Cross-Platform_Content/Configuring_the_Defa...

[cfemfrl]

I did see that, and perhaps read too much into "Blocked Splash page is static and is not customizable at this time" and assumed the article was outdated.

The reason I did is that the block splash page on an MX is in fact customizable as I mention, and the article does not address "Meraki hosted" vs. custom (self) hosted.

Still, I suspect the MX's Blocked page isn't customizable when the splash is custom hosted. At least, I can't figure it out but hoped someone here has.