I've found a bug which changes some arrow directions when using "skinparam linetype ortho".
Example:
@startuml
class "A" {
}
class "B" {
}
"A" #-up-^ "B"
@endumlworks as expected:

On the contrary:
@startuml
skinparam linetype ortho
class "A" {
}
class "B" {
}
"A" #-up-^ "B"
@endumldraws the line from B to A:

It happens with any kind of origin symbol on the arrow (#,*,||...), but works fine without origin symbols:
@startuml
skinparam linetype ortho
class "A" {
}
class "B" {
}
"A" -up-^ "B"
@endumlrenders:

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