As we know high grass is popular place to hide MHQs. Gives good visual protection and (unfortunaly) also magical protection against damage. That is how is goes. But now there has been new issue. Some times you cannot enter vehicle that is inside high grass (do not get option to get in). That is of course a problem when you try to drive EMHQ out to be destroyed or need to move MHQ to new location.
This issue has been at least on Pefkas Bay layout. Have you added thickness of high grass on this layout? So like more high grass object overlapping each other.
From your change log "Pefkas Bay: Added more elephant grass MHQ hidespots...". So that must be it.
(some might call it elephant grass)